Tenth Amendment Center: War Powers: The Difference Between a Declaration of War and an AUMF
An Authorization to Use Military Force (AUMF) is not the same as a declaration of war. An AUMF is the Congress abdicating its power and allowing the president to usurp it. More importantly, it allows the president to start a war.
The declaration of war power does not allow Congress to start a war. It allows Congress, consistent with the non-aggression principle, to declare a state of war exists. This interpretation is supported by 100% of the previous declarations of war by Congress. For example:
When James Polk asked Congress to declare war on Mexico in 1846, he said,
“But now, after reiterated menaces, Mexico has passed the boundary of the United States, has invaded our territory and shed American blood upon the American soil. She has proclaimed that hostilities have commenced, and that the two nations are now at war.
As war exists, and, notwithstanding all our efforts to avoid it, exists by the act of Mexico herself, we are called upon by every consideration of duty and patriotism to vindicate with decision the honor, the rights, and the interests of our country. . . .
In further vindication of our rights and defense of our territory, I invoke the prompt action of Congress to recognize the existence of the war, and to place at the disposition of the Executive the means of prosecuting the war with vigor, and thus hastening the restoration of peace.” [emphasis added]
After reviewing Polk’s request, Congress issued the following declaration of war,
“Whereas, by the act of the Republic of Mexico, a state of war exists between that Government and the United States: Be it enacted by the Senate and House of Representatives of the United States of American in Congress assembled, That for the purpose of enabling the government of the United States to prosecute said war to a speedy and successful termination…”
Note the emphasized words. The state of war already exists because of the act of the Republic of Mexico.
This blog is an excerpt of the 2011 post, What’s So Important About a Declaration of War? and is reposted here with permission of the author.