The tweets. Oh, the tweets! The heads of some of the most powerful countries on Earth are pissed at each other. And they are so angry they're tweeting about it.

Well, they're not really pissed at each other, it's more like they're collectively pissed off at President Trump. And yes, really, who can blame them?

"The American president may not mind being isolated, but neither do we mind signing a 6 country agreement if need be," France's Emmanuel Macron huffily tweeted in French (and then in English for good measure), as the G7 opened in Canada. Later he tweeted a picture of himself with other European heads of state, captioned "Opening the #G7Charlevoix with my European friends." Get it? His European friends. Not you, Donald! Emmanuel Macron is too proud to be friends with a spray-tanned demagogue like Donald Trump (except when he hopes he can swindle him out of some trade concessions). As you may have heard, the rest of the summit did not go much better for Western alliances.

Now, these guys really make it easy to mock the Bravo-ization of international relations. But there's a serious point in all this.

Some of the people who were most shocked by Trump's election reside in European capitals. And they have been processing it through a comical version of the stages of grief: denial, bargaining, and so forth. We're pretty clearly in the anger stage right now.

Except that this anger is not cashing out in any concrete action.

This is all the more regrettable given that Trump's attitude toward Europe is awfully realistic.

The institutions linking together Europe and the United States were critical during the Cold War, at a time when Europe was a much larger share of the global economy, and when it was crucial for America to keep Europe on (relatively) good terms to halt the spread of communism. So the U.S. extended friendly trade terms and the nuclear and military umbrella of NATO. But these conditions no longer obtain.

I was recently invited to one of those semi-secret high-level summits where politicians and high-level technocrats talk about the state of the world and big ideas. The European senior-level people were united in being appalled by Trump, but also in the belief that Trump's anti-Europe posture was only a much more brash, flashy version of what the United States would be doing anyway. More than a few opined that, in a way, Europe was lucky to have the Trump wake-up call, because even a future administration, Democratic or establishment Republican, would be likely to go in the same direction.

You'll recall, after all, that the big theme of Obama's foreign policy was the pivot to Asia. More than a few grumbling Eurocrats pointed out that if you look at a map, you'll see that America pivoting to Asia means America pivoting away from Europe. Obama officials reassured their European counterparts that what was meant was pivoting away from ill-considered Middle East adventures, which was certainly part of it (how did that work out, by the way?), but then spoke to journalists on background and said that, yeah, Europe just doesn't matter all that much anymore, and American diplomacy would be well-advised to focus away from it and on major emerging markets like China and India.

Fair enough. China certainly matters a lot more today than it did in 1945.

But it all brings me back to the tweets. If this is all going on, what are Europeans doing about it, other than complaining?

Well, not much. Take trade. Trump is protesting about trade deficits and threatening tariffs and trying, however haphazardly, to renegotiate trade deals. China is working hard to turn all of Asia, and large parts of Africa, into its economic backyard, with its gigantic "One Belt One Road" initiative which includes new financial institutions, zillions of dollars of infrastructure projects, joint research programs, and all sorts of other initiatives.

What is Europe doing? Tweeting, mostly.

Take climate. Trump wrecked the Paris deal. What's next? Well, by golly, you can be sure that people will hold meetings and put out press releases.

Take defense. Again, Trump is right: Europe has been free-riding on U.S. defense spending, and it is ridiculous that none of the major European countries (for the record, Estonia is pulling its weight) can meet NATO's 2 percent of GDP spending target, which is a rather low bar. After yet another Trump tirade on NATO, Angela Merkel sniffed, as if delivering a eulogy, that Europe must now take its defense into its own hands — and then promptly delivered further cuts to defense spending, which in Germany hovers around 1 percent.

Being subsidized by the American military umbrella is very convenient for Europe, letting it spend more on social programs and then lecturing Americans about underfunding their own welfare state, but it is not necessary. Vladimir Putin won't invade Poland if Europe decides to take its defense into its own hands and politely send the Americans home. France has enough nukes to deter Russia. And as for conventional forces, Russia's GDP is smaller than Spain's, let alone Europe's as a whole, so if it wanted to Europe could absolutely, all by itself, put up an army big enough to put the fear of God into any resident of the Kremlin.

It just doesn't want to. Which, again, makes a lot of sense from a certain perspective. But it does make the complaining ring hollow.

So, Europe: If you really mean everything you say about Trump, put your money where your mouth is! Or shut up. At this point, I'll take either. But please just pick one.