ALEXANDER J. MOTYL is professor of political science at Rutgers University-Newark.

If the leader of the self-styled Donetsk People’s Republic (DNR) has anything to say about it, the current cease-fire [1] in eastern Ukraine [2] will never translate into permanent peace. Nor will it lead to the separatist territories’ reintegration into Ukraine. Alexander Zakharchenko’s statements before and after the guns went silent on the first of September reveal a continued rejection of Ukraine, a commitment to Donbass independence, a strong determination to acquire more territory, and a radical division of people into friends and enemies. Small wonder that separatist violations of the cease-fire have increased [3] significantly since early November.

It is impossible to say whether Zakharchenko’s militancy is the posturing of a desperate man or the vision of a ruthless leader. Either way, it suggests that the DNR’s interests are incompatible with Ukraine’s and that the Minsk-2 accords will fail to achieve their intended goal of reintegrating the DNR and its sister entity, the Luhansk People’s Republic (LNR). Even if Russia [4] pressures the DNR to make substantive concessions—and that is an extremely big if—its leader will resist.

In effect, peace in eastern Ukraine is dependent on two willful, demagogic, unpredictable, and militaristic men—Russian President Vladimir Putin and Zakharchenko. Putin claims to be a bystander in the war, whereas Zakharchenko insists that he is in charge. The reality is more complex. As the September 1 cease-fire showed, Putin’s is the decisive voice. He started the war, and he can sue for peace. But Zakharchenko isn’t just a puppet. He has ideas, ambitions, and plans of his own, and his acquiescence will ultimately determine whether any deal holds.

Zakharchenko, a 39-year-old former electrical mechanic, first entered politics in 2010 [5], the year Viktor Yanukovych was elected president of Ukraine. As head of the Donetsk-based pro-Russian and pro-Soviet organization, Oplot (Bulwark), he actively opposed the Euromaidan Revolution of 2013­–14, was one of seven armed men who seized the Donetsk city administration building on April 16, 2014, and was an active combatant in