Former U.S. President Donald Trump will not be an isolationist if he returns to the White House given his overriding goal is to strengthen his country, Sen. William Hagerty, a strong backer of the likely Republican nominee, suggested Thursday.

Hagerty, a Republican who served as U.S. Ambassador to Japan under Trump, said he talked to the former president last week about the importance of the relationship with Tokyo in maintaining stability in the Indo-Pacific, including in dealing with China and North Korea.

"People misinterpret the term America first" as a byword for a Trump administration seeking to disregard cooperation with the United States' longtime allies, Hagerty said in a group interview with several Japanese media outlets.

Sen. William Hagerty gives an interview in Washington on Feb. 29, 2024. (Kyodo)

Hagerty, a member of the Senate Committee on Foreign Affairs, pushed back on the idea that the United States was isolationist when Trump was in office, saying his job at the time in Tokyo was to make the bilateral alliance as robust as possible.

"Trump has been clear that he wants to see our partner nations as strong as they possibly can be and as supportive as they possibly can be," he said, asserting that media coverage on the former president often distorts the truth, including recent remarks on NATO that sparked alarm with member nations.

He said Trump "has been very consistent that our NATO allies need to step up and pay their dues."

Trump, the clear front-runner in the Republican presidential primary race, said at a rally in South Carolina on Feb. 10 that as president he told NATO allies he would encourage Russia to do "whatever the hell they want" to member countries that fail to meet defense spending targets.

Hagerty claimed Trump's comments, which sent shockwaves through Europe and beyond, were reported out of context.

"What he was trying to say is if you don't, if you don't step up, Russia is going to have their way because being subsidized (by the United States) is not the right way to play this game," according to the senator who represents the state of Tennessee.

Asked about the possibility of Trump again stepping away from various global and regional systems should he win the November presidential election, the senator said he does not think the former president is opposed to dealing with critical issues on a multilateral basis.

Explaining his view that "the problem with multilateral (engagement) is that it's so hard to get every party to come to the table and if one person doesn't agree it is very complicated," he said, "Trump is a business person just like I am. He wants to see progress and wants to see progress rapidly."

On President Joe Biden's plan to host Japanese Prime Minister Fumio Kishida as a state guest in April, Hagerty said he will be welcomed by the United States with open arms.

Hagerty said he believes "Japan certainly is our strongest ally in the region but (also) in the world. So I think it's entirely appropriate. I'm sorry that it is not happening sooner. But I very much appreciate the fact that we're doing it."

When asked about Kishida's desire to have a meeting with North Korean leader Kim Jong Un, the former ambassador said that is "a positive development."

He said, "I applaud the prime minister for looking for a window of opportunity and his willingness to engage (and) negotiate" with North Korea to resolve the issue of Pyongyang's abductions of Japanese nationals in the 1970s and 1980s.

Despite tremendous difficulties in striking a deal with North Korea and considering that time is running out for many aging families of the abductees, he said it is imperative to aim for a settlement and the United States will continue to support Japan to that end.

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