President Vladimir Putin understands how insurgencies work better than any other Russian leader. We are watching this play out right now in Ukraine.

Before Putin took power, Moscow had long struggled to suppress rebel movements. In the 1980s, for example, the Soviet Union grappled with the Muslim mujahedeen in Afghanistan. Moscow propped up the beleaguered Kabul government with an invasion and occupation — to little avail. After 10 years of grueling conflict, Moscow withdrew, just as the Soviet Union fell apart. A few years later, rebels inflicted another serious blow against the Russian military, in the Russian province of Chechnya. Chechen militants launched attacks deep into Russia. The Kremlin again withdrew its forces and essentially sued for peace.

Until Putin took the helm.

Putin succeeded where others had failed because he was skilled at fighting dirty. As a former KGB operative, he fused together intelligence and military measures. In Chechnya he relentlessly pursued the rebels, often using undercover operations that adopted terrorist tactics, until one Chechen leader switched sides and helped him defeat the rebels.

Now in Ukraine, Putin has turned the tables. He is with the insurgents, not the government. Putin is to Kiev what the mujahedeen and the Chechens were to Kabul and Moscow, respectively. Given Russia’s own simmering national minority troubles and territorial disputes, the Russian president is taking a huge risk in backing an armed rebellion in a neighboring country.

But the risk is well calculated because the stakes are high. Putin has a great deal riding on this.

He firmly believes, as he has laid out in many statements, that the battle for the Donbass region of eastern Ukraine is a proxy war with the West. The United States and Europe seek to weaken Russia, Putin’s argument goes, by pulling a key Russian ally, Ukraine, into their sphere of influence. Putin’s goal is to deny Kiev the chance of associating with the European Union and the North Atlantic Treaty Organization.

In Putin’s view, the West stoked regime change in Kiev in February 2014 for the same reasons that the United States supported the mujahedeen in Afghanistan in the 1980s — to undermine Moscow’s authority throughout the region. Putin also asserts that the West aided and abetted the Chechens throughout the 1990s and into the 2000s to destabilize the Russian Federation. So according to Putin’s logic, Afghanistan was the West’s proxy war with the Soviet Union. Ukraine is the West’s proxy war with Russia.

This being a proxy war, Putin is intent on helping the side that best serves Russia’s interests. In this case, that side is the “armed formations,” as the February Minsk agreement describes them, of Ukraine’s Donetsk and Lugansk regions.

Putin, of course, denies that Russians are fighting with the Donbass rebels. Kremlin officials insist this is a civil war between Ukraine and people who reject the new Kiev government. Putin does admit, though, that many Russian volunteers have joined the rebels, including “vacationing” soldiers. Yet Putin has also claimed that Kiev is being supported by “NATO’s foreign legion” and U.S. arms.

The Minsk agreement refers to the presence of “foreign armed formations, military technology, and likewise mercenaries” in Ukraine, without specifying their origin. The denials and the voluntary nature of the external involvement are all hallmarks of a civil war centered on an insurgency.

Having fought off an insurgency himself, Putin knows a thing or two about insurgents’ methods. Putin and the Russian military have incorporated these tactics into a larger strategy of 21st-century hybrid war. Valery Gerasimov, chief of staff of the Russian armed forces, rolled this out in a January 2013 speech. He announced the Russian military would engage in a “new kind of war” fought with “nonmilitary methods to achieve political and strategic goals.”

These methods, Gerasimov explained, would involve fomenting popular protests, using covert military measures and deploying special operations forces, often under the guise of peacekeeping or crisis management. Such tactics, Gerasimov insisted, had been used by the United States for decades. Now Russia would fight back in the same way.

Because of what Putin perceives as an asymmetry of military capabilities and economic strength between Russia and the United States and its Western allies, he feels Russia has to be more aggressive and smarter than its opponents in fighting this new kind of war. This asymmetric, hybrid war, Gerasimov noted, requires “the close coordination of military, intelligence and information operations.”

Russia’s military intelligence, the GRU, and the Federal Security Service have been at the forefront of operations in Crimea and eastern Ukraine, as many observers have noted. Russian diplomats and media have helped to maintain a coordinated information-support campaign to persuade domestic and foreign audiences of “the futility of [exerting] any forms of pressure on the Russian Federation and its allies.” Gerasimov, in another speech in February 2014, explained that this was also a goal of hybrid warfare.

Putin and the Russian military hierarchy have been remarkably open in describing how the Kremlin is using the war in Ukraine as a giant training exercise for conducting a hybrid war. While the rebels have directly engaged the Ukrainian army in the Donbass, the Russian military has been engaged in training exercises just inside Russian territory. These exercises include the use of space, missile and nuclear forces, special forces and conventional military units, and psychological operations teams and political operatives.

They have pulled in all branches of Russia military and security services, as well as the civilian leadership. The exercises have been covered widely in the Russian media and on Moscow’s official websites. In a May 2014 announcement, for example, the Kremlin stated, somewhat cryptically, that Putin was overseeing these giant war games “in operational mode.”

So where are we now in this giant war game? On Feb. 24, we appeared to enter what Moscow might term a “political-diplomatic phase.” This was the first full day without casualties since the Feb. 12 Minsk agreement. As Gerasimov asserted in his speeches, the goal of an asymmetric hybrid war is to achieve objectives without launching a full-blown conventional military war. Hybrid war has many weapons and many ways of fighting.

Diplomacy can be one of them. In late January, the United States government debated whether to send arms to the Ukrainian military. The intent was clearly to push Putin from covert to overt support of the rebels — and into a conventional war. Instead, however, Putin was able to push the U.S. debate into the background by plunging into diplomatic negotiations with the Ukrainian president, the German chancellor and the French president — which ultimately resulted in the second Minsk agreement.

The agreement, in spite of its references to foreign fighters, maintains Russia’s position that the war in Ukraine is between Kiev and the Donbass “armed formations.” The arrangement also provided enough diplomatic cover for the rebels to rout the Ukrainian army from the town of Debaltseve, a railway hub that connects Donetsk and Luhansk.

The timing and wording of the agreement’s provisions that Putin directly hammered out provided sufficient strategic ambiguity for the rebels to press their advantage. As Gerasimov noted a year ago, “political-diplomatic and foreign economic measures … are … closely interconnected with military, information, and other measures.”

Now that the rebels have consolidated their area of control, one operational phase of the game seems to have concluded. Putin bought time for the rebels to take Debaltseve. With the rebels having secured a position of strength on the ground, the ceasefire can now be enforced.

In the next phase, Putin and the rebels will likely regroup. They will pocket whatever concessions they can take from Kiev. They will then likely reassess what they need to do militarily, politically and economically in the next phases of the proxy hybrid war to maintain pressure on Ukraine and the West.

This sort of tactical maneuvering is something Putin learned in the KGB. As circumstances change, you step back and see how everyone else reacts. You have to be willing to adapt and have a range of backup plans to keep one step ahead of your adversaries.

If the military part of an operation runs into a problem, for example, try another approach. If diplomatic efforts don’t bear the fruit you want, look elsewhere. You just have to be willing to use all methods available — and be ruthless to achieve your goals.