King Charles set for historic address to Congress in first US visit as monarch

King Charles III will address a joint meeting of Congress on Tuesday during his U.S. state visit marking America’s 250th birthday, stepping into a high-profile ceremonial moment as Washington remains on edge over heightened security concerns and tensions tied to the war with Iran.

The four-day trip is stacked with various events and private meetings, and comes during escalating pressure on security in Washington, D.C., following the shooting at the White House Correspondents’ Dinner that targeted President Donald Trump and his administration officials. 

Queen Elizabeth II was the first monarch to deliver a speech at the U.S. Capitol during a state visit in 1991, two months after the end of the Gulf War, hammering down the importance of transatlantic alliances in her speech. 

Former advisor to Prime Minister Boris Johnson Thomas Corbett-Dillon told Fox News Digital that Elizabeth famously received three standing ovations during her speech. "The biggest [applause came] after quoting President Abraham Lincoln: 'government of the people, by the people, for the people.'"

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Elizabeth's speech emphasized the importance of transatlantic alliances. 

"We, like you, are staunch believers in the freedom of the individual and the rule of a fair and just law," she said during her address more than 30 years ago. "These principles are shared with our European partners and with the wider Atlantic community. They are the bedrock of the Western world."

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The war in Iran backdrops the visit this week. 

"Her late majesty praised the U.S. for leading our two nations coalition during the Persian Gulf War," said Corbett-Dillon. "The king, of course, will have no such praise for U.S. forces operating in the Gulf, because the U.K. has so far refused to support the U.S. in its war."

Trump has expressed frustration with Britain’s refusal to fully join the U.S. campaign against Iran, and has urged U.S. allies to get involved militarily or operationally, particularly around protecting oil shipments in the Strait of Hormuz.

"This is not Winston Churchill we are dealing with," Trump said on March 3, referring to British Prime Minister Keir Starmer. "By the way, I’m not happy with the U.K. either," the president continued, referring to Starmer blocking the United States’ use of U.K. bases to launch attacks on Iran.

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Corbett-Dillon predicted the speech would be "non-political," but predicts Charles may slip in a few remarks about climate change and protecting the environment. 

"The palace seem to have decided is not a political issue and allows the king to openly and often discuss," he said. 

Trump has repeatedly dismissed climate change as a "hoax," while his administration has prioritized U.S. energy independence by accelerating domestic oil and gas production.

"The king’s one goal from this speech is to maintain unanimous applause from across the House," said Corbett-Dillon. "If he leans too hard into the Green agenda, he may face an embarrassing moment where half of the House stands and applauses while the other half remains seated."

"Many of the American people won’t like hearing the Green Agenda, often seen as a globalist talking point, being pushed to Congress by a foreign king," he added.