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War and Constitutional Separation of Powers

The U.S. Constitution divides war powers between the president and Congress. The delegates to the Constitutional Convention were focused on creating a government powerful enough to protect liberty, but not so powerful that it would threaten liberty. They worked carefully to craft the war powers of the new government, knowing that history was full of examples of war, so that war powers were necessary, but also of rulers who had abused the power and endangered liberty in order to make war.

War Powers of Congress

The powers of each branch of government reflect the roles and virtues of each branch, and this is especially true when it comes to war powers. Of the three branches, Congress holds the greatest number of powers when it comes to war. It is the only branch that can declare war, and it has the power to make funding and many other decisions about how war will be conducted. As the Constitution says:

In part, Article I, Section 8 states that, “The Congress shall have the power…

  • “To constitute tribunals inferior to the Supreme Court;
  • “To define and punish piracies and felonies committed on the high seas, and offenses against the law of nations;
  • “To declare war, grant letters of marque and reprisal, and make rules concerning captures on land and water;
  • “To raise and support armies, but no appropriation of money to that use shall be for a longer term than two years;
  • “To provide and maintain a navy;
  • “To make rules for the government and regulation of the land and naval forces;
  • “To provide for calling forth the militia to execute the laws of the union, suppress insurrections and repel invasions;
  • “To provide for organizing, arming, and disciplining, the militia, and for governing such part of them as may be employed in the service of the United States, reserving to the states respectively, the appointment of the officers, and the authority of training the militia according to the discipline prescribed by Congress;
  • “To make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this Constitution in the government of the United States, or in any department or officer thereof.”

Unlike the president, members of the Senate and House of Representatives are elected by the people (or, in the case of the Senate, the state legislatures prior to the passage of the Seventeenth Amendment).

The Convention delegates reasoned that Congress was made up of many different people, representing different parts of the country, and would, in theory, be more likely than a single individual to be deliberate and prudent rather than impulsive and careless. Therefore, they decided, it should be the branch to have the grave responsibility for declaring war, and even for conscripting (drafting) individuals to serve in the military against their will.

War Powers of the President

In contrast with Congress’s powers, the war powers of the president seem much more limited on paper.

Article II, Section 2 states that, “The President shall be Commander in Chief of the Army and Navy of the United States, and of the militia of the several states, when called into the actual service of the United States.”

The president is commander in chief of the military forces.

This means that once war was declared, the president is be in charge of fighting it. The delegates at the Constitutional Convention made this decision because an individual is more suited to quick responses, energetic action, and swift decision-making than is a large body like Congress.

Alexander Hamilton wrote in Federalist No. 70 about the importance of en energetic executive when it came to protecting the liberty and safety of the people: “Energy in the Executive is a leading character in the definition of good government. It is essential to the protection of the community against foreign attacks; it is not less essential to the steady administration of the laws… to the security of liberty against the enterprises and assaults of ambition, of faction, and of anarchy” (Alexander Hamilton, Federalist No. 70, 1788).

It is not really feasible to fight a war “by committee” as Americans, including both George Washington and Thomas Jefferson, discovered during the Revolutionary War. An individual commander in chief is not only more easily able to act, but also more clearly accountable.

And yet, even an “energetic” president would not be like a king. In all of his roles, including as commander in chief, the president would need to be able to act decisively yet remain within the limits of the Constitution, where specified powers and clear checks and balances could help to constrain a bad president—and also a good president.

Congress holds many of these checks on the president’s war powers. Article I, Section 8 gives to Congress the power of the purse. This power to approve the military budget serves as an important check on the actions of the president. Congress can constrain an unwise commander in chief by cutting spending for a war. As a further check on the power of the central government, military funding decisions have time limits to protect the people from a bad House of Representatives. Specifically, “no Appropriation of Money to that Use [to raise and support Armies] shall be for a longer Term than two Years.”

Changes in War Powers

 In 1941, the Congress declared war on Japan following the attacks on Pearl Harbor. Less than weeks later, they passed the War Powers Act of 1941 allowing the president the power to use executive agencies in the war effort. A few months later, the Second War Powers Act was passed by Congress in order to increase the war-related production of goods. The second act also allowed census data to be used to identify Japanese-Americans who were later interred at relocation camps.

While the War Powers Acts of 1941 and 1942 increased the powers of the president during times of war, the War Powers Act of 1973 sought to curtail the president’s power following conflicts in Korea and Vietnam. Under the Act, the president must inform Congress when he commits troops in emergency situations, and those troops may only remain in combat for up to sixty days without a formal declaration of war by Congress. The War Powers Act of 1973 is still hotly contested. Some see it as a change in the checks and balances between the branches of government as set in place by the Constitution while others believe that the president needs to have the power to act in emergencies.

A Dependence on the People

 Finally, as an all aspects of self-government, the people provide the most important check on government power. Even Madison, the architect of the Constitution’s checks and balances, knew that such protections were just secondary precautions.

“A dependence on the people is, no doubt, the primary control on the government,” he wrote in Federalist No. 51 (James Madison, Federalist No. 51, 1788).  The other checks on government are what Madison called “auxiliary precautions” because the people may be misled by demagogic leaders.

The people are checks on bad government through regular elections. The president must be elected every four years, and—since the passage of the Twenty-Second Amendment—cannot be elected to more than two terms. He can also be impeached. Members of Congress must face their constituents for reelection every two years (in the House of Representatives) or every six (in the Senate). No free government will last without virtue in the people, and in all cases citizens have the responsibility to do their best to choose wise leaders and ensure that bad ones do not return to office.