All of this is, or should be, deeply disturbing; what would the news media be saying if major figures in the Democratic Party routinely praised leftist dictators? But what we’re now seeing from Mr. Trump and his associates goes beyond emulation, and is starting to look like subservience.

First, there was the Ukraine issue — one on which Republican leaders have consistently taken a hard line and criticized Mr. Obama for insufficient action, with John McCain, for example, accusing the president of “weakness.” And the G.O.P. platform was going to include a statement reaffirming this line, but it was watered down to blandness on the insistence of Trump representatives.

Then came Mr. Trump’s interview with The New York Times, in which, among other things, he declared that even if Russia attacked members of NATO he would come to their aid only if those allies — which we are bound by treaty to defend — have “fulfilled their obligations to us.”

Now, some of this is Mr. Trump’s deep ignorance of policy, his apparent inability to understand that you can’t run the U.S. government the way he has run his ramshackle business empire. We know from many reports about his stiffing of vendors, his history of profiting from enterprises even as they go bankrupt, that he sees contracts as suggestions, clear-cut financial obligations as starting points for negotiation. And we know that he sees fiscal policy as no different; he has already talked about renegotiating U.S. debt. So why should we be surprised that he sees diplomatic obligations the same way?

But is there more to the story? Is there some specific channel of influence?

We do know that Paul Manafort, Mr. Trump’s campaign manager, has worked as a consultant for various dictators, and was for years on the payroll of Viktor Yanukovych, the former Ukrainian president and a Putin ally.

And there are reasons to wonder about Mr. Trump’s own financial interests. Remember, we know nothing about the true state of his business empire, and he has refused to release his taxes, which might tell us more. We do know that he has substantial if murky involvement with wealthy Russians and Russian businesses. You might say that these are private actors, not the government — but in Mr. Putin’s crony-capitalist paradise, this is a meaningless distinction.

At some level, Mr. Trump’s motives shouldn’t matter. We should be horrified at the spectacle of a major-party candidate casually suggesting that he might abandon American allies — just as we should be horrified when that same candidate suggests that he might welsh on American financial obligations. But there’s something very strange and disturbing going on here, and it should not be ignored.