This is stated in Johnson's oped for the Daily Mail, Ukrinform reports.
"I simply cannot believe that Trump will ditch the Ukrainians; on the contrary, having worked out, as he surely has, that there is no deal to be done with Putin, I reckon there is a good chance that he will double down and finish what he started — by giving them what they need to win," Johnson wrote.
The ex-prime minister recalled that in 2014, after the Russian invasion of Ukraine, Trump was one of the first leaders to provide the Ukrainians with Javelin anti-tank missile systems, which - together with the British NLAWs - were "so valuable to the Ukrainians in the battle for Kyiv."
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"So, whatever they now say about President Trump, I cannot believe that he will want to go down in history as the president who abandoned a country that he has already signally helped to keep free," the politician noted.
He added that the war in Ukraine is "the paramount struggle of our time, and we are still not doing enough to help that heroic nation."
"They can, must and will win," Johnson wrote.
The former prime minister added that Trump would certainly demand that the Europeans pay more for their own defense, but this is a long-standing U.S. policy.
"To all his Ukraine-sceptic supporters in the Republican Party, I say: how can you possibly make America great again if you allow a Russian tyrant to inflict a total humiliation on the West?" Johnson wrote.
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As Ukrinform reported earlier, despite the fact that the exclusion of Donald Trump from electoral rolls was initiated in 34 American states, he remains far ahead of his Republican rivals in public polls ahead of primaries.
Earlier, Trump pledged to put an end to the war in Ukraine "quickly" if he wins this year’s presidential election because he "gets along very well" with Russian President Vladimir Putin.
