Kevin McCarthy, now House speaker, warned in October that a GOP majority would not write a “blank check” to Ukraine, a statement widely interpreted as opposition to continued US support for Kyiv’s defense against Russia’s invasion. He was echoed by various rank and file, including some in the GOP caucus with clear sympathies for Russian President Vladimir Putin.

This week, Florida Gov. Ron DeSantis joined the choir, denouncing President Joe Biden’s “blank-check policy with no clear, strategic objective identified.”

Has the party of Reagan finally parted ways with the Gipper’s staunch internationalism? Actually, and for the most part, no. Rather, the Biden administration bears much of the blame for eroding bipartisan backing for Ukraine because the president has failed consistently and repeatedly to articulate a strategy or an endgame for US support.

The wisdom of US aid for Ukraine seems manifest: Putin is a threat to the United States and the NATO alliance. He has invaded Ukraine twice, annexed swaths of territory and been pushed back by the almost superhuman efforts of the Ukrainian people.

There are no US “boots on the ground.” The cost to the US taxpayer — less than $100 billion — is not even a quarter of what Biden wants to spend on his illegal student-loan-forgiveness stunt. And the reward — the defeat and humiliation of a dangerous nuclear-armed would-be hegemon — is immeasurable, costing no blood and manageable treasure.

Despite a clear understanding of the critical importance of standing with and arming Ukraine, the Biden administration and many of America’s NATO allies have slow-rolled military support to Kyiv, flip-flopping on deliveries of critical equipment that could shorten the course of the conflict and save lives. In fact, notwithstanding protestations of unwavering support, Biden last year allowed $2 billion in drawdown authority — the budget mechanism that’s sourcing US weapons for Ukraine — to simply expire with the fiscal year’s end.

As to difficult questions about the long-term aims — will NATO support the reconquest of Crimea, occupied and annexed in 2014 by Russia, for example? — Team Biden has remained stubbornly silent. In his visit to Kyiv this week, the first anniversary of the war, Biden said, “Unchecked aggression is a threat to all of us,” as close as he got to articulating any strategy or game plan. Is it any surprise polling shows only 48% of Americans now support us arming Ukraine?

Enter Ron DeSantis. Widely believed to be a 2024 presidential candidate, DeSantis has played his foreign-policy cards close to the vest. The public knows him as an ardent culture warrior, a lockdown opponent and the scourge of an increasingly woke Walt Disney. But his national-security views are shrouded, and even his short stint in the House of Representatives reveals little.

So why leap onto the stage with the “blank check” line? Simple. No one wants to give Joe Biden a blank check.

Take the statements from McCarthy and DeSantis as delivered. Will the United States keep appropriating taxpayer funds should the Ukraine war drag into the years? Indeed, perhaps it should.

But will members of Congress armed with little more than gauzy assurances that this is the battle of “democracy vs. tyranny” be game to continue pouring money into that war even as public support erodes? Will Republicans looking at a persistently confused US policy be willing to simply sign on the dotted line with faith the Biden administration will do the right thing?

DeSantis’ full quote is revealing: “They have effectively a blank-check policy with no clear, strategic objective identified, and these things can escalate, and I don’t think it’s in our interests to be getting into a proxy war with China, getting involved over things like the borderlands or over Crimea.”

Parsing the answers to DeSantis’ questions: Yep, the Biden administration has failed to articulate a “strategic objective.” And Joe Biden himself has warned of “Armageddon” should Russia choose to escalate with nuclear weapons. On China, Secretary of State Antony Blinken just warned Sunday that Beijing is “strongly considering providing lethal assistance to Russia.”

There’s more, relative to the “borderlands” DeSantis mentions: Russian missiles have overflown Moldovan airspace several times, and Moscow is engaged in an aggressive campaign to destabilize its small neighbor. Moldovan President Maia Sandu has asked America for more support against Russia. And finally, there’s Crimea.

For many, Russia’s illegal annexation of Crimea should not stand. Certainly, there appears little reason the West should distinguish somehow between one part of Russian-occupied Ukraine over another. Perhaps Biden hopes to negotiate away Crimea in exchange for a Russian capitulation on the remainder of Ukraine.

But that ambiguity is opening the door to further questions about US strategy and concerns that an effort to retake Crimea will extend the conflict between Moscow and Kyiv, requiring additional commitments of time and cash from Europe and the United States.

Is the Biden administration weighing all this in the balance? Or dithering as usual? If Washington is indeed “all in,” it’s time to start explaining that to the American people.

In short, while the subtext behind DeSantis’ questions might be troubling — is he a J.D. Vance or, worse yet, a younger, smarter Donald Trump? — the questions he asks are far from outrageous. And it would behoove the president of the United States to answer them — now.

Danielle Pletka is a distinguished senior fellow at the American Enterprise Institute.