A small number of lawmakers criticized Israel and urged Washington to stay out of the conflict.

Shortly after the start of the Israeli attack on Iranian nuclear facilities, military bases, and residential buildings early on Friday morning, Senator Lindsey Graham (R-SC) posted on X, "Game on. Pray for Israel."

Graham led a chorus of largely Republican lawmakers who called for prayers for Israel as it attacked Iran.

Some lawmakers hoped the war would bring down the Iranian government. "The threat from Iran will only stop when the regime is destroyed," Rep. Carlos A. Gimenez (R-FL) said. "Anything less is just a temporary respite from the existential threat Iran poses to our allies and the free world."

Many US lawmakers claimed that Israel's preemptive attack on Iran was an act of defense. "Make no mistake: Israel is not the aggressor. It is defending itself against an existential threat that long predates the present preemptive strike. The true aggressor is the Islamic Republic and its empire of terror—an empire stained with the blood of innocent Israelis," New York Democrat Ritchie Torres wrote on X. 

Other members of Congress, including Rep. Jimmy Panetta (D-CA), framed the Israeli strikes as "defensive."

Rep. Mike Lawler said the Israeli strike was "justified," but added that the US should attack Iran should it retaliate. "Let there be no doubt, we will defend our ally Israel, our other partners in the region, and our military and diplomatic personnel. Iran should understand that there will be grave consequences for any actions they take in response to this justified strike on their nuclear facilities," he said. 

A frequent argument made by members of Congress is that the Israeli attacks are justified by the supposed nuclear weapons threat posed by Tehran.

"Iran has greatly expanded its uranium enrichment with the goal of producing nuclear weapons that pose an existential threat to Israel," Maine Republican Senator Susan Collins wrote. "Our country too is at risk as Iran continues its development not only of fissile material but also of ballistic missiles. I hope the Israeli operation to eliminate Iran's nuclear capability is successful."

However, top intelligence officials in both the Trump and Joe Biden administrations repeatedly stated that Iran was not attempting to develop a nuclear weapon. During recent nuclear talks with Washington, Tehran said it was willing to agree to caps on its energy program to ensure it was only used for civilian purposes.