The two-hour virtual summit between President Biden and Vladimir Putin, held Tuesday in the midst of very real worries about full-scale war, ended as expected: without a breakthrough.

Nothing Putin said — not his concerns about NATO expansion or his claims about Russia’s historical ties to its southwestern neighbor — was enough to push the American president off his public commitment to Ukrainian sovereignty and territorial integrity, or off his refusal to let Russia decide whether Ukraine may join NATO. And it remains to be seen whether Biden’s threats of sweeping sanctions “and other measures in the event of military escalation,” as the White House readout put it, will be enough to reverse the march of some 175,000 Russian troops to the Ukrainian border — or whether they will spur those forces on still further.

More than at any other time since modern Russia emerged from the debris of the Soviet Union 30 years ago this month, Western policymakers need a clear-eyed view of how and why the Kremlin makes political decisions — which makes it all the more troubling that so much of the debate about the summit and the troops ignores the things we do know, focusing instead on things we cannot know.

There are those, for example, who suggest that the Kremlin’s aim is conquest pure and simple, driven by Putin’s alleged desire to reconstitute the Soviet Union and his belief — expressed in an essay published under his name in July — that Russia and Ukraine are destined for unity. Others peg Putin’s dreams a notch lower, pointing to his assertion that any Western deployment of weapons or soldiers to Ukraine would cross a “red line” and lead to a forceful Russian response. Still others note his speech to the senior Russian diplomatic corps last month, in which Putin spoke approvingly of the “anxiety” that Russian saber-rattling had caused in Western capitals and called for more of the same — seemingly suggesting that all of those other things he said were just for show.

The problem with taking Putin’s words seriously is figuring out which of his words were seriously meant. And to do that, it makes sense to look at his political interests. During his 22 years in power, it’s become clear that Putin’s actions map pretty well onto what will benefit him politically.

We know what Putin’s domestic political motivations might be. His overriding interest is in maintaining and cultivating his power; that focus often crowds out concerns about the future and his legacy. The archives of Putin’s speeches are littered with grand promises and even good ideas, many of which — such as shifting the economy away from natural resources, making the police more accountable to citizens or breaking up powerful monopolies — were abandoned because they threatened his power base. It turns out that, like most politicians, Putin is willing to sacrifice long-term goals for short-term survival.

For all of Putin’s vaunted authoritarianism, we know that he relies on popular support to make his power effective and durable. Being popular — or popular enough — means he can spend less money on the police and worry less about challenges from within his own elite. As a result, he doesn’t generally do things that he knows the Russian public will disapprove of.

We know that there are limits to Putin’s ability to manipulate public opinion. While the Kremlin’s TV and online propaganda machines are formidable, they can’t change the way people think and feel about the things that matter to them most — especially the economy.

And we know that when Putin does decide to go on an adventure abroad, he tries very hard to minimize the costs to him at home. When possible, this means making his wars short and sweet: Think Russia’s five-day invasion of Georgia in 2008, or the virtually bloodless annexation of Crimea in 2014. When protracted war is unavoidable, Putin’s Kremlin gets others to fight for him, whether proxies (as in the Donbas, which is part of Ukraine) or mercenaries (in Syria, Libya and the Central African Republic).

Put these things together, and we have a much clearer view from Putin’s vantage of what might happen in the current showdown. Whatever ambitions Putin may harbor for restoring Russian greatness or reconquering Ukraine, he is not likely to pursue those goals at the expense of his own power.

But would Russian public opinion reward him for such an adventure?

It is true that the annexation of Crimea gave Putin four years of stratospheric approval ratings of over 80 percent, even as the Russian economy tanked. A large-scale invasion of Ukraine, however, would be very different. It would involve massive numbers of regular Russian troops, not a few thousand “little green men,” proxies or mercenaries, and many of those troops would die. It would bring immediate and sweeping sanctions onto an economy that is already struggling to cope with the pandemic and inflation — at a time when 44 percent of Russians already say the country is headed in the wrong direction. And however much Putin might believe that Russians and Ukrainians should share a government (presumably his), and no matter how much he talks about it on TV, only 17 percent of his compatriots share that opinion. (Even fewer Ukrainians do.)

Does that mean war is impossible? No. But if Putin does invade Ukraine, he will do it without broad public support at home, and in a manner that will almost certainly weaken that support still further. It would break just about every rule in a playbook that has ensured his political longevity.

Clearly, though, detente between the United States and Russia is also not in the cards. As focused as Russians are on the economy, most also see the United States as a geopolitical threat, and Putin has successfully used that threat to marginalize the domestic opposition and independent media, branding them as traitors. Short of disbanding NATO, nothing Biden could say or do would change that state of affairs.

So where does that leave the United States and its allies? What we know about how Putin uses and maintains power suggests that radical shifts — whether toward war or toward reconciliation — are unlikely, which means a long period of confrontation is all but inevitable. Western governments can’t change that reality, but they can learn to live with it. They can insulate themselves and Ukraine from the worst of its effects, and relearn the kind of strategic patience that a protracted conflict requires.