Before yesterday's military operation targeting nuclear enrichment sites in Fordo, Natanz and Isfahan, rifts were beginning to form within the party over the prospect of the US joining Israel to stop Iran from developing a nuclear weapon.

Trump had campaigned for his second term opposing US involvement in the Middle East, promising to adopt an "America first" approach if elected for a second term.

He had also previously criticised the then-president Barack Obama, posting to social media that he would start a war with Iran because of his "inability to negotiate properly" and to "save face".

Last week, Trump indicated Iran would have two weeks before he decided on whether to support Israel's efforts in Iran, but broke his own deadline after announcing the US had completed a "spectacular military success" in Iran.

Within minutes of the news, strong condemnation began to roll in.

Kentucky Republican Congressman Thomas Massie, who has been leading a War Powers Resolution to prevent the US from becoming involved in another Middle East war in a rare cross-party alliance with California Democrat Congressman Ro Khanna, criticised the strikes as unconstitutional.

"Congress has the sole authority to authorise war. Speaker Mike Johnson should bring our resolution to the floor for a vote immediately," he said on X.

Georgia's Republican Congresswoman Marjorie Taylor Greene, a far-right conservative and staunch Trump supporter, opposed the country's involvement.

"Every time America is on the verge of greatness, we get involved in another foreign war," she said on X.

"There would not be bombs falling on the people of Israel if Netanyahu had not dropped bombs on the people of Iran first. Israel is a nuclear-armed nation.

Ohio Republican Warren Davidson said it was "hard to conceive a rationale that's constitutional".

He later questioned when Congress would be weighing in on the matter.

Trump, however, insisted he had the full support of the Republican Party.

"Great unity in the Republican Party, perhaps unity like we have never seen before," he said on Truth Social.

Democrats have condemned the President for ordering the strikes without approval from Congress, which they say went against Article I of the Constitution.

"President Trump came into office promising to 'end the endless foreign wars.' Tonight, he took steps that could drag the United States into another one, without consulting Congress, without a clear strategy, without regard to the consistent conclusions of the intelligence community, and without explaining to the American people what's at stake," Democratic Virginia Senator Mark Warner said on X.

"The Constitution makes clear that the power to authorise war lies with Congress."

New York Democrat Alexandria Ocasio-Cortez went further to claim that Trump's strikes were "grounds for impeachment".

But one of the top Republicans in Congress, House Speaker Mike Johnson, said Trump had evaluated that the "imminent danger outweighed the time it would take for Congress to act".

"The President fully respects the Article I power of Congress, and tonight's necessary, limited, and targeted strike follows the history and tradition of similar military actions under presidents of both parties," he said on X.

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