The democratic model is a model in which the legislative branch has the power to decide whether to go to and declare war. As Table 1 shows below, 26 (20.47% of 127) nations follow the democratic model:

The War Powers Clause of the United States Constitution is the first and most typical clause of this model. As James Wilson explained, “It will not be in the power of a single man, or a single body of men, to involve us in such distress; for the important power of declaring war is vested in the legislature at large” (Elliot,

A semi-democratic model is a model in which the legislative branch can decide whether to go to war, and the head of state or the executive branch can declare war with the endorsement of the legislative branch. It differs from the democratic model in that both the legislative branch and the executive branch/head of state are responsible for waging war. In many nations, although the legislative branch can approve the decree deciding whether to go to war, the president or the council has the power to reject (the bill of) the declaration of war. As Table 2 shows below, 68 (53.54% of 127) nations are classified under the semi-democratic model.

In most of these countries, the head of state, such as the king or president, declares war according to the constitutional procedure based on the authorization of the legislative branch. Although the United Kingdom does not have one specific constitutional document named as such, the prime minister alone has the authority to send troops to war using royal prerogative powers that are decided by the parliament and declared by the queen (Haddon, 2013) . What is worth mentioning is that in Armenia and Sweden, it is not the head of state but the government that declares war based upon the legislature’s decision. In addition, the Netherlands declares war by a royal decree signed by the king and by one or more ministers or state secretaries.

The article also finds that the constitutions of 11 nations have statutes about who decides whether to go to war but do not mention who declares it. These countries are Bangladesh¹⁰⁹, Georgia¹¹⁰, Ireland¹¹¹, Kazakhstan¹¹², the Lao People’s Democratic Republic¹¹³, Macedonia¹¹⁴, Mali¹¹⁵, Mauritania¹¹⁶, Senegal¹¹⁷, Slovenia¹¹⁸, and Venezuela¹¹⁹. However, in these nations, the declaration of war is in the form of decrees or ordinances that are signed and pronounced by the head of state or the leader of government. Thus, they could be seen as a special category of the semi-democratic model. In all, this model includes 26 African nations, 16 Asian nations, 22 European nations, 5 North American nations, 8 South American nations, 1 Oceanian nation and 1 transcontinental nation, 79 (62.2% of 127) in total.

In the semi-democratic model, making war requires the head of state/executive branch and the legislative branch to cooperate and come to a consensus. Otherwise, as shown below, in 63 (79.75% of 79) nations, the head of state or the executive branch could exercise veto power to reject what the legislative branch has approved and return the bill to the legislature: Afghanistan¹²⁰, Armenia¹²¹, Argentina¹²², Azerbaijan¹²³, Bangladesh¹²⁴, Brazil¹²⁵, Bulgaria¹²⁶, Burkina Faso¹²⁷, Cape Verde¹²⁸, Chad¹²⁹, Chile¹³⁰, Colombia¹³¹, Costa Rica¹³², Côte d’Ivoire¹³³, the Democratic Republic of the Congo¹³⁴, Croatia¹³⁵, Cyprus¹³⁶, Djibouti¹³⁷, Egypt¹³⁸, El Salvador¹³⁹, Finland¹⁴⁰, France¹⁴¹, Gabon¹⁴², Gambia¹⁴³, Guinea¹⁴⁴,

Guinea-Bissau¹⁴⁵, Haiti¹⁴⁶, Honduras¹⁴⁷, Italy¹⁴⁸, Kenya¹⁴⁹, the Republic of Korea¹⁵⁰, Kyrgyzstan¹⁵¹, Latvia¹⁵², Lithuania¹⁵³, Maldives¹⁵⁴, Mexico¹⁵⁵, Myanmar¹⁵⁶, Netherlands¹⁵⁷, Niger¹⁵⁸, Nigeria¹⁵⁹, Portugal¹⁶⁰, Rwanda¹⁶¹, Sao Tome and Principe¹⁶², Sierra Leone¹⁶³, Slovakia¹⁶⁴, Sudan¹⁶⁵, Tanzania¹⁶⁶, Thailand¹⁶⁷, Timor-Leste¹⁶⁸, Togo¹⁶⁹, Tonga¹⁷⁰, Tunisia¹⁷¹, Uganda¹⁷², Ukraine¹⁷³, Uzbekistan¹⁷⁴, Georgia¹⁷⁵, Ireland¹⁷⁶, Kazakhstan¹⁷⁷, the Lao People’s Democratic Republic¹⁷⁸, Macedonia¹⁷⁹, Mali¹⁸⁰, Mauritania¹⁸¹, and Venezuela¹⁸². In many of these countries, despite rejection by the head of state, if the bill or draft referring to war-making can be approved again by a supermajority of two-thirds of the legislature such as the parliament, congress, or national assembly, the bill is considered endorsed and enforceable. In addition, in some nations such as Ireland, the exercising of veto can put a bill or draft law by the legislative branch to a vote by referendum. These provisions, of course, further increase the prudence and deliberation of war-making.

As the name suggests, in the dictatorship model, a single person (usually the executive head of state) has nearly unlimited power to initiate war, while the legislative and executive branches can usually pose very limited restrictions on him/her. As Table 3 shows below, 18 (14.17% of 127) nations follow the dictatorship model (listed in alphabetical order).

In such nations, the legislature can participate in the process of deciding whether to go to war only by providing advice to the head of state, such as through an advisory committee. For example, in Mozambique, the Council of State shall compulsorily advise the President of the Republic on war and peace affairs whenever the President requests such advice. Correspondingly, the duty of the executive head of state is to notify and inform the legislature with clarifications

whenever the interest and the security of the nation thus allow. In this model, there are usually very limited restrictions on those with the powers of making war. In some nations, such as Algeria, Angola, and Burundi, before declaring war, the president should consult with the legislature. For example, in Algeria, before declaring war, the president has to convene the Council of Ministers, hear the High Council of Security and consult with the President of the Council of the Nation and the President of the People’s National Assembly. In Zimbabwe, although the president has the power to declare war, there is a rejection process by which the Senate and the National Assembly, by a joint resolution passed by at least two-thirds of the total membership of Parliament, can resolve that the declaration of war should be revoked. In short, this model insists that an individual judgement would be superior to a collective judgement, which may cause the nation to go to war without a political consensus. Moreover, without a required bargaining process, the head of the state would have no obligation to explain why war was necessary to the public, who would ultimately bear its cost. An empirical study shows that democracies are highly effective and indeed more successful than those dictatorship nations in similar circumstances (Schultz, 2001) .

Meanwhile, as Table 4 shows below, there are 63 (32.98% of 191) nations whose powers to decide whether to go to and declare war have not been regulated by their constitutions.

In brief, in 63 nations, including powerful military nations such as Russia, India, and Pakistan, waging a war may not require constitutional authorization by a widely preventive collective.

Statistical data show that 23 (21.9% of 105) nations have special procedural requirements for making the proposal to wage a war. As Table 5 shows below, there are 3 major categories: proposal by the president, proposal by the government and proposal with mandatory consultation requirements. In the first category, the president’s proposal to make war is the prerequisite before the legislature makes the declaration of war. In the second category, the legislative branch declares war following a government proposal. In the third category, consultation with specific executive organs such as the council of ministers or the national defence council or relevant reports by executive organs is the prerequisite for a decision of war made by the legislative branch.

Four nations cannot be classified as above. In Morocco²²⁰, the declaration of war takes place after communication of the king to the parliament. InIraq²²¹, a joint request from the President of the Republic and the prime minister is the prerequisite of the declaration of war by the Council of Representatives. In Sudan²²², the proposal of making war is made by the president with the consent of the first vice president. In Macedonia²²³, either the president or the government or at least 30 representatives can make such a proposal. In Cape Verde²²⁴, the government’s request and consultation with the council are required before a decision of war is made.

The next question is who has the power to approve the war bill/decree. Before going to war, nations typically engage in what is known in the literature as crisis bargaining, a communicative process of signalling about capabilities and resolve (Reiter, 2003) . As Table 6 below shows, with the exceptions of the 18 nations of

the dictatorship model and the 64 nations without constitutional provisions on the powers to decide whether to go to war and declare war, most of the remaining 109 nations can be divided into 5 major types according to the distribution of the power to decide whether to go to war. Type 1 could be labelled “both houses jointly”, in which the adoption of a war bill/resolution requires the two chambers/houses of a nation with a bicameral legislature to meet as the congress/parliament in a joint public session and all members of the legislature to vote. Type 2 could be labelled “the lower house” in which the lower house of a bicameral legislature has the power to decide whether to go to war. Type 3 could be labelled “the upper house” in which the upper house of a bicameral legislature can decide whether to go to war. Type 4 could be labelled “the single house” in which the single body of a unicameral legislature has the power to decide whether to go to war. Type 5 could be labelled “the government” in which the government can decide whether to go to war.

Nevertheless, two nations cannot be classified into a certain type above. In the United Arab Emirates³³¹, a war bill is approved by the Supreme Council, which is the highest legislative and executive body. In Côte d’Ivoire³³², the Parliament has the power to decide whether to go to war; however, in case of disagreement between the two houses, the decision is made by the National Assembly (the lower chamber).

In addition, in 17 (15.6% of 109) nations, declaration of war requires a stricter voting basis³³³ than other legislative processes. In Luxembourg³³⁴, Uganda³³⁵, Egypt³³⁶, Mali³³⁷, and Guinea³³⁸, a two-thirds majority vote of the all members of the only house of the legislature is required. In Hungary³³⁹, such a decision requires the vote of two-thirds of the present members of the only house. In Slovakia³⁴⁰ and Tunisia³⁴¹, the decision of war demands a three-fifths majority vote of all members of the single house. In Philippines³⁴², Czech Republic³⁴³, Georgia³⁴⁴, Uruguay³⁴⁵, Madagascar³⁴⁶, Thailand³⁴⁷, and South Sudan³⁴⁸, such decisions are approved by a vote of two-thirds of both houses assembled in a joint session. In Iraq³⁴⁹, such a decision requires a two-thirds majority vote of the lower house. In Lebanon³⁵⁰, such a decision requires the vote of two-thirds of the government members. Supermajority rules can “prevent the government from becoming an engine for producing private interest goods” (McGinnis & Rappaport, 1999) , including political ambitions, thus providing an effective contemporary mechanism for controlling the war powers.

Deciding on and declaring war constitutionally and prudently requires chiefly that the legislature consistently perform its constitutional duty to decide whether to initiate war. In total, 32 (29.36% of 109) constitutions have designed so-called “exceptional clauses” in case of the absence of the legislature and urgent cases³⁵¹. If the legislature or its permanent/standing committee is prevented from taking decisions or an urgent case arises, according to the exceptional clauses, war powers may be vested in a particular political person or body of the executive branch. As Table 7 below shows, such clauses can be divided into 4 categories:

in the first category, if the legislature is not able to meet, the head of state such as the king or the president may decide whether to declare war and take steps for the protection of the nation without the authorization of the legislature. The second category is the same as the first, except that the head of state must submit these decisions for approval in the next sitting of the legislature. In the third category, if the legislature is not able to meet, the government or a special department may decide whether to go to war and take steps for the protection of the nation without the authorization of the legislature.

Three nations, however, cannot be classified into one of these categories. In Croatia³⁸¹, in case of an immediate threat, the president with the counter signature of the prime minister may order the employment of the armed forces. In Czech Republic³⁸², the Senate shall declare war when the Assembly of Deputies is dissolved. In Serbia³⁸³, the decision of war shall be passed by the president together with the President of the National Assembly and the prime minister when the National Assembly cannot be convened.

By keyword analysis of the 191 constitutions in force, 160 constitutions were found that have clauses on the designation of a commander-in-chief.³⁸⁴ In 154 nations (96.25% of 160 constitutions), the power of the commander-in-chief of the armed forces is vested in the head of state including executive and non-executive persons, such as the president, the prime minister, or the queen. It is worth mentioning that in Bosnia and Herzegovina, the three-member presidency³⁸⁵ is the chief, and each member of the presidency shall have civilian command authority over the armed forces. As Table 8 below shows, 6constitutionsdo not vest the head of state but others with the power of commander-in-chief.

As the statistical data show, most of the modern constitutions have reached a consensus that a single person as commander-in-chief, not a collective or group, shall make all expeditious and coordinated tactical decisions necessary to wage war successfully (Turner, 1984) . Thus, in most nations, the constitution authorizes the commander-in-chief to identify and respond to foreign threats, using such force as he/she deems necessary. However, the abuse of the powers of the commander-in-chief since World War II, to some extent, has promoted a return to authoritarianism in making war and resulted in modern undeclared wars.

With the return to authoritarianism in war-making, in the process of making war, the legislature is eclipsed by the commander-in-chief who often doubles as the head of state. Recognizing that war is the most serious decision a leader can take, such a return would allow what the framers of the United States and later constitutionalists tried to guard against: a single person making the war decision even when there has been no real attack on the nation and there is ample time for a collective, deliberative, and accountable decision by the legislature.

The return in the United States is typical. A review of history can show how the return has come about. Historically, the United States Congress has declared war only five times³⁹². Nevertheless, Since World War II, the United States has been involved in almost one hundred military conflicts³⁹³ without the declaration of war, of which the Korean War was the first. In 1947, as the Cold War began, the

United States created the office of the Secretary of Defense, the Joint Chiefs of Staff, the National Security Council, and the CIA. Each of these reported to the president, greatly enlarging his authority over national security. Later presidents, however, contended that they did not need congressional authorization to use force (Garcia, 2012) . The legitimacy of such unauthorized wars has spurred debate in the United States and around the world. Congress tried to settle these disputes by passing the War Powers Resolution in 1973, which was intended to check the president’s power to commit the United States to an armed conflict without the consent of Congress. It stipulates that president can send United States Armed Forces into action abroad only by declaration of war by Congress, “statutory authorization”, or in case of “a national emergency created by attack upon the United States, its territories or possessions, or its armed forces.” Since then, however, presidents and some researchers have consistently maintained that parts of the resolution intrude unconstitutionally on the president’s war powers (Turner, 2012) . It is widely believed that the War Powers Resolution has been violated several times since its entry into force (The Constitution Project, 2005) . Many congressional leaders have argued that the executive branch has failed to abide by either the constitutional limitations on presidential authority or the provisions of the resolution (Goldstein, 1988) .

The return in the United States has had worldwide influence. Since World War II, more commanders-in-chief in presidential democracies have emulated the United States by winning more independent powers to initiate war in struggles with the legislature by waging undeclared wars, which severely challenge the legitimacy of the war powers clauses.

The large number of undeclared wars since World War II, as a result of the return mentioned above, have challenged the traditional constitutional control over war. A declaration of war is a formal document that promises war against another nation or proclaims that a state of war already exists. Article 1 of the Hague Convention (III) demands that states shall issue a declaration of war before the commencement of hostilities. The declaration of war had legal effects such as changing the rights of neutral parties or the relationships between states.

However, since World War II, the legal obligation of a declaration of war has been mostly ignored. The “Malayan Emergency” set by the United Kingdom was the first modern war without a formal declaration. As mentioned above, since 1941, the United States has not formally declared war. Moreover, a number of nations have followed these examples and characterized limited warfare and pre-emptive or preventive military actions as a “military action” or “armed operation”. The most recent undeclared war was the Russian military intervention in Ukraine. In addition, the rapid growth and spread of terrorist crimes around the world poses a serious threat to the peace and security of the international community. However, according to the traditional definition, a war is fought between sovereign states, and most terrorist attacks are committed by international terrorists and criminal groups that are non-state actors. Theoretically, there may be no need for a traditional declaration of war on terrorism.

Today, declarations of war have become so meaningless that, while the legislature can authorize war, a collective, deliberative, and accountable decision by the legislature is not necessary for a commander-in-chief to wage an undeclared war. By undeclared war, the commander-in-chief can bypass the constitution and wage a real war instead of taking up only the legal duty to make day-to-day tactical decisions. Complementarily, the undeclared wars in recent years have given the commander-in-chief more room to make decisions with the lack of collective supervision. As Lori FislerDamrosh argued, “Presidents who are weak in their domestic political posture, but who believe themselves to possess very potent and essentially unchecked war powers, are the most dangerous of all.” (Damrosh, 1995) . The return of authoritarianism in war-making and undeclared wars are creating opportunities for those leaders while eroding the legitimacy of the legislative branch in war-making.