Last year, months before the United States killed a senior Iranian commander in a dramatic escalation of tensions in the Middle East, bipartisan majorities in both the House and Senate voted to limit President Donald Trump’s ability to go to war with Iran.

The language never actually made it into law, marking another defeat for lawmakers in both parties who have clamored to reassert Congress’ constitutional authority to declare war since the sweeping war authorizations of 2001 and 2002 that have been used to justify American military incursions since then.

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But the fact that the votes took place at all shows that the prospect of war with Iran — an outcome made much more likely by the U.S. drone strike Thursday that killed Gen. Qassem Soleimani, leader of the covert Quds division of Iran’s Islamic Revolutionary Guard Corps — weighs heavily on the minds of many lawmakers.

Even had it passed, a congressional authorization for use of military force, or AUMF, on Iran would not necessarily have precluded the killing of Soleimani, which Pentagon and other administration officials have described as a preemptive response to an imminent threat to American personnel in Iraq.