Donald Trump boasts ‘it was not pleasant’ for countries that underestimated US military - during speech in Japan

President labelled 'insensitive' over remarks made in nation where America killed around 140,000 people with atomic bombs in Hiroshima and Nagasaki

Donald Trump has risked causing major offence during a visit to a key US ally, with bellicose remarks to troops that talked up America’s military prowess.

The President was speaking at Yokota air base in Japan in the early stages of his tour of the Asia-Pacific region and at a time of heightened tension with North Korea due to the country’s nuclear ambitions.

Mr Trump has traded insults with Kim Jong-un, who he calls “Little Rocket Man”, following repeated ballistic missile tests by Pyongyang including two that flew over Japan’s Hokkaido island.

The billionaire did not temper his rhetoric in a speech to US and Japanese military personnel on Sunday, saying that “together with our allies, America’s warriors are prepared to defend our nation using the full range of our unmatched capabilities”.

“No dictator, no regime, no nation should ever underestimate American resolve,” he added.

And in a remark that held the potential to cause widespread offence in a country where America killed around 140,000 people in 1945 – when it dropped atomic bombs on Hiroshima and Nagasaki – the President added: “Every once in a while, in the past, they underestimated us. It was not pleasant for them, was it?”

Dr Jacob Parakilas, the deputy head of Chatham House’s US and the Americas programme, told The Independent the remarks were “insensitive”, but arguably no more so than other comments the President is reported to have made about Japan.

“This at the same time that he described them as a nation of ‘samurai warriors’. I think that’s probably much more offensive,” he said.

He added: “It’s a question of what the Japanese people feel. The Japanese government isn’t likely to raise a concern over anything that Trump says that they perceive as insensitive, because they’re seeking his continued support.

“It’s Trump. He barely can get through a day without saying something that’s readable as impolitic.”

Mr Trump was reported to have told allies he could not understand why Japan, as a nation of “samurai warriors”, did not shoot down North Korea’s missiles as they flew over its home islands.

The US President made the comment in phone calls or meetings with Southeast Asian leaders in recent months, according to the Japan Times.

Experts have said that while technology exists to shoot down ballistic missiles, it is not perfect and a failed attempt could hand Mr Kim “an incalculable propaganda victory”.

On Sunday Mr Trump met with Japanese Prime Minister Shinzo Abe for golf and a relaxed discussion of regional affairs.

The pair will move to formal talks in Tokyo on Monday where Mr Abe will look to present a united front against North Korea, and seek reassurances that the US will keep its treaty obligations to defend Japan if attacked.

The President’s tour will also take in South Korea, China, Vietnam and the Philippines.

Ahead of the visits the US moved a third aircraft carrier strike group into the western Pacific in a show of strength – aimed not just at North Korea but at China, according to experts.

Mr Trump will hope to persuade Chinese premier Xi Jinping to exert more pressure on Pyongyang to abandon its nuclear programme.

Trade will also feature heavily during the trip as the President tries to persuade Asian allies to agree to policies more favourable to the US. Mr Trump pulled out of the Trans-Pacific Partnership, a multilateral trade deal, calling it “a potential disaster for our country”.

A centrepiece of the trip will be a visit to the Asia Pacific Economic Cooperation summit in Danang, Vietnam, where he will deliver a speech in support of a free and open Indo-Pacific region, which is seen as offering a bulwark in response to expansionist Chinese policies.

“One of the things we’re going to be very focused on is trade because trade has not been done well for 25 years by the United States with this part of the world, with any part of the world,” he said on Air Force One.

“We’re going to be discussing reciprocal trade. Fair, free but reciprocal,” he said.