If President Obama follows the practice of post-WWII presidents, he may use military force without consultation or authorization from Congress. If President Obama follows the letter of the War Powers Resolution, he may use military force for 60 to 90 days without congressional authorization. If President Obama follows the Constitution, he must secure congressional authorization before using military force. Presidents of both parties have not been held to constitutional standards for several decades. Authorization has shifted from Congress to the president, as presidents since Truman have commenced military operations virtually at will, and some have claimed that authority flowed from commander-in-chief responsibilities or from the UN or NATO.
The Constitution. Very little in the Constitution is as clear as the delegation of war powers. Only Congress has the authority to declare war, and only the president commands in war. Even Alexander Hamilton, who favored a strong president, proposed that the Senate "have the sole power of declaring war" and that the executive "have the direction of war when authorized or begun." But presidents were expected to repel invasions without consultation or authorization. Repelling invasions included preemptive war, but preemptive war requires an imminent threat of attack with existing capability and all other options exhausted -- e.g., troops on the border to attack at dawn.
In the language contemporary to the constitutional debate, general war and perfect war were expressions used to describe the condition when opposing states were mobilized for war. But there was also common language -- limited war, imperfect war, or partial war -- used to describe military force used to pursue limited objectives. Declarations of war were associated with the former, and authorizations for the use of force were for the latter. Both were the exclusive domain of Congress.
The logic was quickly confirmed and clarified in Supreme Court rulings. In 1800, the Supreme Court ruled in Bas v. Tingy that only Congress could authorize war whether perfect or imperfect. "Congress is impowered to declare a general war, or congress may wage a limited war; limited in place, in objects, and in time." In the 1801 Talbot v. Seeman case, Chief Justice Marshall wrote that "The whole powers of war being, by the Constitution of the United States, vested in congress ... the congress may authorize general hostilities ... or partial war."
From George Washington forward, presidents have been successfully consolidating their power over foreign affairs and the use of military force. We could retrace the rise of presidential war from Washington forward, but let's start with Harry Truman. Truman sent troops to Korea without asking for or receiving congressional authorization. Troop levels rose to over 300 thousand, and over 36 thousand were killed. Congress was generally in favor of the policy and allowed the president to get away with an impeachable offense.
Eisenhower is the only post-WWII president to treat Congress as a full partner in the use of force. He asked for and received advanced authority to use force against China if it threatened Taiwan. He asked for and received advanced authority to use force to resist "international Communism" in the Middle East. Under considerable political pressure, Eisenhower refused to intervene militarily on behalf of the French in Vietnam. He did so by establishing three preconditions for US involvement: US allies would have to provide forces in equal numbers, the French would have to grant independence to Indochina, and the U.S. Congress would have to declare war. He knew that none of these would obtain, and certainly not all three.
- Section 3 requires the president to consult with Congress prior to introducing forces into hostilities. It's unclear who in Congress should be consulted.
- Section 4 requires initial reporting within 48 hours and follow-on reports at least every six months.
- Section 5 specifies timelines. Specifically, forces initially deployed under presidential authority must be withdrawn within 60 days after the initial report to Congress, but only if the report cites section 4(a)(1).
In the ongoing context of the breakup of Yugoslavia, Clinton threatened air strikes against Serbia in support of the ethnic Albanians. That course of action was opposed by Russia and China and likely would have produced a veto in the UN. Without UN sanction, and without congressional authorization, Clinton ordered air strikes.
Congress attempted to constrain the president's use of force and to prevent deployment of ground forces. Eighteen members of Congress filed suit in federal district court to force the president to get authorization for the air war. The House passed a bill to prohibit funds for ground forces without prior authorization. Additional measures were considered to limit the expenditure of funds. A proposal in the House to declare a state of war against the Federal Republic of Yugoslavia was almost unanimously defeated. In the Senate, John McCain's proposal to authorize all uses of force was defeated. Still, Congress submitted for presidential signature an emergency supplemental with billions for operations in Kosovo.
As the 60th day passed since commencement of the air war and no 30-day extension had been requested. The president cited the alleged constitutional defects of the War Powers Resolution. Both the House and Senate considered authorizing air and missile strikes. The Senate leaned toward air operations. The House was split. No prohibitive or authorizing legislation was passed.
The constitutional process had worked its way to completion and denied the authorization to use force. Clinton continued air operations regardless. It was the "first time in our history that a president has waged war in the face of a direct congressional refusal to authorize the war."
- Presidents use force without asking for or receiving congressional authorization, report a fait accompli and call it consultation, reject the WPR as nonbinding, and claim the constitutional authority to use force without congressional authorization.
- Congress, usually the opposition party, mounts an ineffectual resistance. Congress "supports the troops" through appropriations but "rejects the policy" by refusing authorization.
- The Courts refuse to adjudicate claiming that these legislative challenges to the president are political matters rather than constitutional.