On Monday and Tuesday, Russian planes and helicopters flew very, very close to the USS Donald Cole, a destroyer operating in the Baltic Sea.

How close? This close:

The Russian planes were flying at the US ship in the same way they would be if they were conducting an attack run. Thankfully, they were unarmed — but the act was needlessly, dangerously provocative. What's more, Russia has been doing this for years, even buzzing the Donald Cook roughly 12 times two years ago, when it was in the Black Sea.

Why does this keep happening? It's hard to know for sure, of course, without listening in on Russian orders (which unfortunately I have so far been unable to do). But given what we know about Russian foreign policy in the Putin era, these overflights make a lot of sense.

Putin, you see, has elevated aggressive geopolitical trolling to the level of doctrine. Needless provocations aimed at signaling "strength" have become a hallmark of Russia's foreign policy in the Putin years. These actions are buzzy and generate a lot of breathless coverage in the American press, but they often offer little in the way of actual strategic value for Russia — and indeed often risk scary escalation.

In other words, the USS Donald Cook overflights aren't an aberration. They're a perfect metaphor for much of Russian foreign policy under Putin: loud, buzzy, dangerous, and not actually all that great for most Russians.

Putin's trolly foreign policy

Examples of dangerous Russian provocations abound. In September 2014, Russian soldiers abducted an Estonian intelligence officer. Estonia is a NATO member; the abduction happened just two days after President Obama gave a speech vowing to defend Estonia and other Baltic NATO states from aggression.

That same year, Russian warships violated Latvian waters (another Baltic NATO member) 40 times. Russia has also made a habit of flying planes near or over the Baltics with their transponders switched off — making it hard to ascertain whether their intentions were peaceful. Some of those planes were nuclear-capable strategic bombers.

We've seen similar behavior in the Middle East. During Russia's intervention in Syria, Russian planes repeatedly violated Turkish airspace. This continued even after Turkey shot down a Russian plane in November 2015. Turkey is — you guessed it — a NATO member.

The point is that these sorts of low-level military provocations have become routine parts of Russian foreign policy — it's just something Putin does.

Why? Putin appears to see these provocations as a way to intimidate his adversaries in the West — namely, the US and NATO. The basic theory is that if he signals a willingness to risk conflict, the West will back down. Going to war with Russia would be objectively insane, so the idea is that if Putin seems crazy and eager to pick a fight, his adversaries won't be willing to risk it over, say, Ukraine or Syria — issues that are important but certainly not worth going to war with Russia over.

"His calculation appears to be that the scarier he seems, the more political traction he has," Mark Galeotti, a professor at NYU who studies Russia, wrote in a February piece for Vox. "What the Kremlin does have is the will to take risks, ignore the rules, and hope that the other side is more sensible, more cautious, more willing to make concessions than it is to call Russia's bluff."

According to Galeotti, this is an attempt to do as much as Russia can with what little it has. The Russian military is weak, despite a significant Putin-directed initiative to repair it. Its political institutions are deeply corrupt. Its troubled economy is oil-dependent and hurtling toward disaster.

Russia has very few tools to advance its interests, in other words — so Putin has decided that flashy trolling is a way to make the most of it.

Ukraine shows the limits of this strategy

When Putin's troll theory has been tested in practice, however, it has been left wanting. Ukraine is by far the clearest example.

The two highest-profile Russian foreign policy moves of late, the interventions in Ukraine and Syria, both testify to the limits of Putin's troll doctrine — albeit in different ways.

In Ukraine, Putin has succeeded in seizing effective control of Crimea, as well as creating a "frozen conflict" in the Donbas region of eastern Ukraine. But it's not actually clear why this is good for Russia. Retaking Crimea has been a longtime ideological goal of Russian nationalists, and controlling the territory theoretically helps secure the valuable naval base in the city of Sevastopol. But on the whole, these aren't exactly massive strategic gains.

And the eastern Ukraine conflict has turned into an outright debacle. Hundreds, if not thousands, of Russian soldiers have died; the Russian government spends $40 million a month on pensions alone for its proxy government in Donbas.

Maybe this would be worth it if Putin's intimidation campaign had convinced Western countries to roll over and cede Ukraine to him. But the opposite is the case. The US and its European allies responded with punishing sanctions, depriving Russian businesses of much-needed foreign capital. According to International Monetary Fund estimates, the sanctions likely knocked off somewhere between 1 and 1.5 percent of Russian GDP after they were implemented — a pretty hefty sum.

And more broadly, neither Putin's trolling exercises nor his Ukraine intervention has weakened Western military resolve. A new report from a consortium of European think tanks found that defense spending on the continent will jump 8.3 percent in 2016 — a break with a consistent post–Cold War pattern of declining European defense spending. The think tanks see "Russia’s aggressive posture epitomized by Moscow’s illegal annexation of Crimea and the crisis in Ukraine" as a direct cause of this spending hike.

The point, then, is that Putin's brinkmanship has not yielded a pliant Europe, one willing to bend to Russia's interests in Ukraine and elsewhere. In actuality, it has led to significant economic pain, a renewed anti-Russian alliance in the West, and little in the way of meaningful strategic gains.

Russia's Syria intervention is an exception

In Syria, Russia launched an intense campaign that lasted only six months before Putin announced a drawdown. The tactical goal of the escalation was clear: reversing the battlefield momentum against Russia's ally Bashar al-Assad. This is the opposite of the Ukraine intervention, an open-ended commitment without an obvious tactical endpoint.

Indeed, the Syria intervention represents an exception to Putin's trolling policy in general. And that's why, in a very limited sense, it kind of worked.

Russian bombing was absolutely vital to the Assad regime's recent gains near Aleppo, Syria's largest city, near Latakia in western Syria, and in the southern Daraa province. These gains have flipped the battlefield momentum, ensuring Assad won't collapse in the near term (as seemed plausible just before the Russian intervention).

So Russia propped up a client regime that the West hates — and the US just sat there and watched. Seems like a success for Putin's trolling strategy, no?

Not so fast. If you look closely at Russia's strategy in Syria, it becomes clear that it's in some ways an abandonment of the trolling strategy Putin has used against the West.

First off, while the military gains Russia secured for Assad were impressive, they haven't actually saved him.

"The Russian intervention does not by itself ensure Assad’s long-term future," the Levantine Group, a Middle East intelligence firm that focuses on Syria, writes in a recent report. Assad is still too weak to win the war on his own, for reasons the report explains:

The over reliance on auxiliary and largely foreign forces has deepened, and while these forces have proven efficient on the offensive, they won’t be sufficient to fill the gaps in Assad’s defense: The regime’s gains actually accentuate the persistent manpower issue, as Assad needs to defend a wider territory.

For the Russian strategy to ultimately succeed, it will need to secure a political resolution, not just a military one — that is, a negotiated end to the conflict in Syria that secures Russia's interests, such as maintaining its naval port in the Syrian city of Tartus. And that won't happen without being able to reach some kind of negotiated settlement with the United States and other regional powers.

Russia recognizes this. That's why Russian Foreign Minister Sergei Lavrov worked with Secretary of State John Kerry to broker a ceasefire afterward, which has at least somewhat succeeded in reducing violence. This wasn't accomplished by intimidating the United States into capitulating, but rather by good old-fashioned diplomacy, where both sides come to agreeable terms based on mutual interests.

Putin's goal in Syria, it's now pretty clear, was to strengthen Russia's hand in negotiations — both with the West, by strengthening the military position of Russia's ally, and with Assad himself, by showing that he depended on Russia's support for survival and thereby creating the leverage to eventually force him to accept a peace deal on Russian terms. In other words, the goal is to secure Russian interests in any peace deal, not to intimidate the West into accepting an Assad victory.

Hence why, in December, Russia voted for a UN Security Council resolution calling for a transitional government in Syria to replace the current regime — something Russia obviously would not have done if the goal were to keep Assad in power.

The strategy here, then, is the opposite of the intimidation strategy Putin is pursuing in Europe. The two share some common objectives — getting the West to recognize Russia as a global power, for example — but this strategy involves leveraging for a compromise rather than intimidating the West into accepting Russian demands. The ends may be somewhat similar, but the means are radically different.

And that is precisely why the intervention in Syria worked.

Why Putin does this: It's good for him

So if Putin's attempt to use provocations to intimidate the West hasn't been all that successful, and comes with real costs, why is he doing it?

There are many answers, including Putin's own ideological view of Russia and its place in the world. But a key part of the story is self-interest: Loud provocations with the West help Putin at home.

Since 2012, Putin has faced a serious legitimacy problem. His reelection bid that year was marred by mass protests and anger at an allegedly rigged game, and the subsequent slowdown of the Russian economy has made it seem like he has little to offer the people.

The solution, as my colleague Max Fisher explains, is nationalism — buy the loyalty of the Russian people by asserting its power on the world stage:

Putin's answer has been to assert Russian power beyond its actual strength — and, in the process, to recast himself as a national hero guarding against foreign enemies. Without a world-power-class military or economy at his disposal, he is instead wielding confusion and uncertainty — which Soviet leaders rightly avoided as existential dangers — as weapons against the West.

Trolling the West is a core part of that. Sending ships into Latvian waters, abducting an Estonian intelligence officer, and — above all — intervening in Ukraine are all ways of asserting Russia's geopolitical dominance, thus showing the Russian people that their country — and their leader — is strong. Indeed, Putin's popularity in Russia has shot up since the Ukraine intervention. (Interestingly, roughly 69 percent of Russians opposed the Syria intervention at the outset.)

Now, this isn't all about popularity: It seems likely, based on what we know about Putin, that he also genuinely believes Russia is a great power that is owed respect from Western countries.

But it's tough to make sense of the flashy, high-profile, and ultimately ineffective ways he's chosen to go about asserting Russian interests without seeing them at least partly through the lens of domestic Russian politics.

Once you understand this, then, Russia's trolling activities — including buzzing the USS Donald Cole — become more comprehensible. They're not acts of dominance, showing how much tougher Putin is than Obama. They're not acts of a madman intent on starting a war.

They're acts of an insecure dictator, equipped with a weak military, doing what he can to assert his place in the world. They're acts of weakness.

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