(Philip Wegmann, RealClear Wire) A year ago, Boris Johnson made people jittery by reporting that Vladimir Putin threatened to fire a missile at him in the run-up to Russia’s invasion of Ukraine. He apparently is no longer worried. Johnson is no longer prime minister of the U.K., and this week he basked in the safety of the United States.

Johnson toured Capitol Hill Tuesday, meeting with U.S. lawmakers not only to press the case that Ukraine needs more military aid to beat back the Russians, but also that they deserve membership in the North Atlantic Treaty Organization.

“I am here primarily to recognize and pay tribute to the immense U.S. contribution to the security of the Ukrainian people. There is no doubt that without the United States it would have been much more difficult for the Ukrainians to have turned the tide of this war,” Johnson wrote in a statement.

The former leader of Britain’s Conservative Party has already met with a number of American conservatives who are predisposed to raise a skeptical brow to the tens of billions of dollars in military financial aid the Biden administration has sent to Ukraine.

A member of his staff told RealClearPolitics that he plans to lunch with the Republican Study Committee Wednesday. Similar meetings for Senate Republicans are also in the works.

“My mission is to demonstrate that Ukraine will win,” Johnson said in a statement to RCP, “and that there is no conceivable case for delay in further supporting the Ukrainians to win this year. We should have no fear of escalation when it comes to the provision of weaponry.”

The United States has rallied the West to support Ukraine, and President Biden has repeatedly pledged to keep that lifeline of financial aid and military equipment open “as long as it takes, so Russia cannot in fact defeat Ukraine and move beyond Ukraine.” But Republicans are increasingly skeptical.

House Republicans report that they were charmed by the former prime minister, but they share the sentiment of Speaker Kevin McCarthy, who promised late last year that there would no longer be “a free blank check.” Particularly worrisome for many of the fiscal conservatives on the Hill? The possibility of corruption and graft in Ukraine.

Rep. James Comer, the Kentucky Republican now chairing the House Oversight Committee, told RCP last week that he plans on combing through receipts for signs of “waste or misuse.”

“With any massive government spending comes the opportunity for waste, fraud, abuse, and mismanagement. Ukraine aid is no different,” Comer told RCP, before adding that Congress owes it “to the taxpayer” to “conduct oversight over the tens of billions of U.S. taxpayer dollars sent overseas.”

The White House insists that U.S. aid to Ukraine has gone where it was intended and been used for its designed purpose. John Kirby, Biden’s national security spokesman, confirmed to RCP that the administration has not seen any misuse of either dollars or bullets so far. Neither military nor financial assistance, he said, “have fallen prey to any kind of corruption in Ukraine.”

While Republican Senate Minority Leader Mitch McConnell has said that supplying Ukraine remains the “number one priority” for most members of his party, some conservatives argue that the focus should be on problems at home. McCarthy himself warned late last year in an interview with Punchbowl News that voters may lose their appetite for generosity if domestic challenges like the border go unaddressed. “Ukraine is important,” he said, “but at the same time it can’t be the only thing they do.”

For America’s European allies, the danger isn’t so far removed. Johnson watched the Russian invasion from his post at 10 Downing Street last year after warning Putin that aggression would lead to sanctions and a more muscular NATO. That is when the Russian president casually floated bringing a missile down on the head of the then-prime minister.

“He threatened me at one point and said, you know: ‘Boris, I don’t want to hurt you but with a missile it would only take a minute,’ or something like that,” Johnson recalled during an interview for a BBC documentary about the war in Ukraine. In his recollection, Putin was just being “jolly.”

“From the very relaxed tone that he was taking, the sort of air of detachment that he seemed to have,” Johnson added, “he was just playing along with my attempts to get him to negotiate.”

The West has been anything but relaxed in their response to Russian aggression. After the U.K. pledged to send tanks to Ukraine and Germany said it would follow suit – but only if the U.S. did as well – Biden announced last week that he would send 31 Abrams battle tanks to Ukraine, armor that the administration hopes will help turn the tide come spring. For his part, Johnson now serves as an unofficial ambassador to keep that aid flowing – and more.

Writing in the Washington Post, the Brit called for Ukraine to officially join NATO, a possibility that the Russians have long found unacceptable.

“The truth is, if you had asked me before Putin’s invasion when Ukraine would join NATO, I would have said, ‘Roughly when hell freezes over, or not for at least 10 years,’” he wrote.

“But then, if you had asked me whether we would now be sending Challenger tanks to Ukraine, or Abrams tanks, or whether the Germans would now be sending Leopard tanks – I would have thought you were mad. Just as I would have thought you were mad if you had told me that Putin was going to invade,” he added.

When Russian tanks started rolling across the Ukraine, Johnson concluded, Moscow’s argument against Kyiv joining NATO went up in smoke: “They had a case once, and they were heard with respect. That case has been pulverized by the bombs and missiles of Putin.”