That argument aside, there are certainly some diplomatic opportunities for Mr. Trump to exploit, although history and recent ominous warnings suggest he could soften up his opponents and allies with threats of military action if he doesn’t get his way. (See: Iran, Greenland, Panama.)

Here’s a scorecard to keep handy for the first few months.

In the fog of war, a potential Ukrainian deal

There is very little evidence that Mr. Putin is eager for a deal to extricate him from a war that has already cost Russia nearly 200,000 dead and more than half a million wounded. But the assumption is that he has to look for a way out. Since his televised debate with Vice President Kamala Harris, Mr. Trump has been promising just that — a deal “in 24 hours,” or even one that will be completed before he takes the oath of office.

Now, unsurprisingly, it looks a little more complicated. His special envoy for Ukraine, Keith Kellogg, an 80-year-old retired general who served on Trump’s first National Security Council, recently told Fox “let’s set it to 100 days” to make sure “the solution is solid, sustainable,” and to end this war so we can stop the carnage.” Mr. Trump said he would meet with Mr. Putin, which is a significant moment, especially because Mr. Biden has not spoken to the Russian leader in almost three years.

What could the deal look like? First, most Biden and Trump officials acknowledge, at least privately, that Russia would likely keep its forces in the roughly 20 percent of Ukraine it now occupies — as part of a truce similar to the one that halted, but did not end, the Korean War in 1953. The hard part of any deal is security agreement. Who would guarantee that Mr. Putin will not use the cessation of hostilities to rearm, recruit and train new forces, learn from the mistakes of the past three years, and invade again?

Jake Sullivan, advisor to Mr. Biden on national security, claims that Biden’s team has spent the past year “putting in place the architecture” to ensure that security. But Volodymyr Zelensky, the Ukrainian president, suspects that it’s all just a story. Recalling that no one paid attention to the 1994 security agreement Ukraine signed with the US, Britain and Russia, among others, he says only NATO membership will prevent Mr Putin from attacking again.