Congress hasn't officially declared war since 1942. Presidents launched these 11 military operations anyway.

A week ago, the United States’ and Israel’s war against Iran passed the 100-day mark.

In the more than three months since the war began, a host of ethical, economic, and political questions have arisen about the conflict.

One of the most pressing political questions has centered on the legality of the war itself.

Operation Epic Fury, a large-scale military operation, was launched without congressional authorization, which lawmakers argue is required under the Constitution.

On June 3, the House of Representatives passed a War Powers resolution that, if passed by the Senate, would require the removal of all offensive forces within 30 days of its passage, per PBS News.

In May, the Senate advanced its own resolution, which hasn’t been brought to a final vote.

The House resolution will require 60 votes in the Senate in order to be brought to a vote.

President Donald Trump would then hold the ability to veto the resolution, which would require a two-thirds vote from both houses to override it.

In May, Trump argued that a ceasefire with Iran meant hostilities were “terminated” and therefore congressional approval wasn’t necessary.

Since Trump’s comments, the US has carried out further strikes against Iran, which government officials labeled “self-defense” strikes, PBS News reported.

Congress hasn’t officially declared war since June 4, 1942, when it declared war on Bulgaria, Hungary, and Romania during World War II.

Since then, in instances like the Gulf War, the war in Afghanistan, and the Iraq War, Congress has typically approved force via “Authorization for Use of Military Force.” While not an official declaration of war, it allows the military to engage in targeted objectives, according to the Library of Congress.

Still, there have been plenty of times throughout American history when the president has ordered large-scale military operations without direct congressional approval, whether through loose interpretations of presidential powers or without providing any legal justification.

While this practice has been met with legal challenges at times, in other instances, presidents have avoided scrutiny from Congress due to widespread support for the military action.

Andrew Wiest, a professor of military history at the University of Southern Mississippi, said these instances are part of a broader concession of Congressional war powers to the executive branch since WWII. “Since 1946, Congress has relinquished this constitutional authority and granted it to the president, probably much to the founders’ chagrin,” Wiest said. “The founders were extremely wary of a president with too much military authority.” Here are 11 notable examples of US military operations conducted without direct congressional approval.