King Charles III is certainly enjoying his reign.

During his state visit, King Charles III delivered a stirring address to Congress on Tuesday, emphasizing the enduring bond between the United States and the United Kingdom and heralding the dawn of a “new era” for the two allies.

King Charles charmed both Republicans and Democrats with his witty remarks, admiration for democratic values, and a strong call to support Ukraine. His speech to the joint session of Congress was met with multiple standing ovations, as he skillfully bridged political divides.

Projecting a hopeful vision for the future of US-UK relations, the king subtly countered past frustrations expressed by President Trump towards the UK government by focusing on unity and the shared values that bind the two nations.

In his nearly 30-minute address, the king highlighted the “irreplaceable and unbreakable” relationship between the US and the UK, urging a renewal of their historic alliance.

He also took a moment to celebrate America’s upcoming 250th birthday, noting that the partnership between the nations was “born out of dispute” but has since flourished.

But he recalled the deep historic and personal bonds — including his mother, Queen Elizabeth’s, speech before Congress in 1991 — and how the partnership has endured even through the most trying times.

“From the bitter divisions of 250 years ago, we forged a friendship that has grown into one of the most consequential alliances in human history,” he said.

“We find ourselves in a new era,” the king said of this “more volatile and more dangerous” time.

“The challenges we face are too great for any one nation to bear alone,” the king said. “But in this unpredictable environment, our alliance cannot rest on past achievements, or assume that foundational principles simply endure.”

The king’s speech comes during a turbulent time in US relations with the United Kingdom, as President Trump has butted heads with British Prime Minister Keir Starmer on numerous issues, particularly over the war against Iran.

And while King Charles didn’t address that conflict directly, he sought to remind that the deep connection between the two nations will outlast current disagreements and governments.

He made note of Trump’s own words: “The bond of kinship and identity between America and the United Kingdom is priceless and eternal. It is irreplaceable and unbreakable.”

He also touted Starmer’s call to build on the “indispensable partnership” between the nations.

“Renewal today starts with security,” King Charles said. “The United Kingdom recognizes that the threats we face demand a transformation in British defense. That is why our country, in order to be fit for the future, has committed to the biggest sustained increase in defense spending since the Cold War.”

Speaking to the shared values of the United States and United Kingdom, the king earned a bipartisan standing ovation when he praised the system of “checks and balances.”

Many members of Congress — Republicans and Democrats — have expressed concern that Trump has engaged in executive overreach and needs to adhere more to the separation of powers.

“The U.S. Supreme Court Historical Society has calculated that Magna Carta is cited in at least 160 Supreme Court cases since 1789, not least as the foundation of the principle that executive power is subject to checks and balances,” the king noted.

And that was not his first bipartisan standing ovation. The king’s impassioned defense of NATO and plea for Ukraine had lawmakers on both sides of the aisle cheering.

“Unyielding resolve is needed for the defense of Ukraine and her most courageous people – in order to secure a truly just and lasting peace,” he said.

Both House Speaker Mike Johnson (R-La.) and former House Speaker Nancy Pelosi (D-Calif.) expressed optimism before the speech that the king would help unify Congress and solidify US-UK relations. Afterwards, lawmakers praised the king’s message as a triumph.

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“The King nailed it,” Sen. Lindsey Graham (R-SC) wrote on X.

“His speech was a much-needed morale boost for Congress.”

Graham, who is a close ally and friend to Trump, added it was a “bit odd” that it took a king to bring them together.

“I believe most members of Congress feel better after the speech than they did before. Though I will admit it was a bit odd that the unifying feeling had to come from the King of England… but so be it!,” he wrote.

The speech is part of a state visit that saw the king and Queen Camilla feted at the White House with a state dinner and celebratory welcome ceremony.

Earlier, Trump expressed his fondness for the royals — and even recalled his late mother’s crush on the king.

“In the centuries since we won our independence, Americans have had no closer friends than the British,” Trump said.

King Charles will head to New York on Wednesday. In his speech to Congress, he reflected on the 25th anniversary of the September 11th attacks and used the moment to stress the importance of NATO.

“We stand with you now in solemn remembrance of a day that shall never be forgotten,” he told lawmakers, adding that it was the first time “NATO invoked Article 5.”  

“United in the face of terror, we answered the call together – as our people have done so for more than a century, shoulder to shoulder, through two World Wars, the Cold War, Afghanistan and moments that have defined our shared security.”

Trump has railed against the alliance, particularly complaining about its lack of aid in the war with Iran. 

But the king said NATO is needed for the defense of Ukraine and for “each other’s defense, protecting our citizens and interests, keeping North Americans and Europeans safe from our common adversaries.”

“Our defense, intelligence and security ties are hardwired together through relationships measured not in years, but in decades,” he reminded lawmakers.

He also offered his personal prayer that the NATO alliance – formed in the Cold War – would survive.

“I pray with all my heart that our Alliance will continue to defend our shared values, with our partners in Europe and the Commonwealth, and across the world, and that we ignore the clarion calls to become ever more inward-looking,” he said.

And, at a time of Trump’s fiery rhetoric, the king had a gentle reminder that America’s words matter.

“America’s words carry weight and meaning, as they have since Independence. The actions of this great nation matter even more,” he said.

He went on to quote Abraham Lincoln’s Gettysburg address: “The world may little note what we say, but will never forget what we do.”

The king condemned political violence in the wake of another Trump assassination attempt on Saturday at the White House Correspondents’ Dinner.

“Let me say with unshakeable resolve: such acts of violence will never succeed,” the king said.

While his overall reception was one of warmth and welcome, there was one area where the king got a more tepid response: his defense of nature.

The king is an avowed environmentalist, but many lawmakers are more skeptical about global warming.

“Our generation must decide how to address the collapse of critical natural systems, which threatens far more than the harmony and essential diversity of nature,” the king said. 

“We ignore at our peril the fact that these natural systems – in other words, Nature’s own economy – provide the foundation for our prosperity and our national security.”