Want a reason war criminal Vladimir Putin never invaded anything under Donald Trump’s presidency?

Simple: Russia had no idea how the Donald would respond. And that was the beauty of Trump’s foreign-policy philosophy — peace through strength but with a splash of ambiguity. The world was a safer place for it. 

Then there is President Joe Biden. He just can’t keep quiet — at least when he can remember what he was going to say, that is.

In nearly every instance, Biden has told the world exactly everything he was going to do when it comes to Russia and its war of aggression on Ukraine. He even told our mortal enemy China about Russia’s plans, for some reason thinking Beijing would help. Perhaps just another senior moment?

So why is our dazed and confused commander-in-chief bothering to go to Brussels for a NATO summit Thursday? He has already told us what he has in mind when it comes to Ukraine: absolutely nothing that will help Kyiv win its war of survival against the Kremlin.

Indeed, the White House has already announced what will happen at the summit — and none of it will help one bit in the here and now. There’ll be “new sanctions” and a “crack down on evasion” of the existing sanctions, national security adviser Jake Sullivan says.

While more sanctions will surely hurt Putin in the long term, in the short term, Ukrainians need assistance that will boost them on the battlefield now.

Speaking of those battlefields, does Biden even have any idea how he can actually help Ukraine keep Russia at bay? He has been clear that he won’t give Ukraine the MiG-29 fighters it’s been begging for. Nor will he implement a no-fly zone to rid the skies of Russian bombers that are slaughtering innocent civilians.

While we can certainly debate the merits of those ideas, Biden just keeps telling us what he won’t do, and that only bolsters Russia’s hope that it can force a settlement on the battlefield. 

There is a clear path Biden could chart that would lead to a summit worth having, doubtful as it seems.

First, the president needs to separate short-term and long-term goals for Ukraine. In the days and weeks ahead, Biden should not only keep sending anti-tank, anti-air and small arms to Ukraine in ever-larger numbers but increase intelligence sharing with Kyiv — in real time if possible — to make sure Russia can’t destroy supply lines. 

And here is where things get even more challenging. Biden needs a long-term strategy to ensure Ukraine has the arms to deter the Kremlin from trying to attack again once Russia’s economy recovers or is greased enough from Chinese assistance.

Many experts have advocated sending Ukraine older M1 Abrams tanks and A-10 Warthogs that are sitting in US military storage facilities. Combine those with Harpoon anti-ship missiles and a modernized air force including F-15EX fighters or even F-35s, and Putin would not think of trying to attack Ukraine ever again.

But Biden also needs to be firm with his NATO allies, just as Trump was, that Europe’s defense must be funded at a level that ensures this will be Russia’s last aggressive act. Germany has clearly stepped up its military spending and should be applauded, but Biden must be clear that America cannot be Europe’s 911 force when a crisis breaks out. Why should America care about Europe’s security if Berlin, Paris or Brussels won’t spend the euros themselves? 

Unfortunately, none of this is going to happen. The world will be treated to globalist toasts to Biden’s new world order — whatever that means — and statements crowing that the NATO alliance is “united” and “ironclad.”

I think the collective free world is sick of hearing that Biden and the West will defend every inch of NATO territory.

Tell us what you have planned, Mr. President, to ensure Putin and his gang of thugs not only lose in Ukraine but don’t keep invading more countries. Either Biden has no plan or he already forgot what it was.

Harry J. Kazianis is the senior director at the Center for the National Interest.

Twitter: @Grecianformula.