Russian President Vladimir Putin is exploiting the tense situation in Syria to his own benefit, Aaron David Miller wrote in the Wall Street Journal of Tuesday.

Putin seems to have seen an opportunity after US and coalition airstrikes over the weekend mistakenly killed at least 62 Syrian government soldiers and wounded a hundred other people–instead of hitting intended Islamic State targets in the Deir Ezzour area in northeastern Syria.

Russia had said on Friday that Washington’s inability to control regime opponents was derailing the cease-fire.

In the wake of the errant airstrike, Moscow called for emergency consultations at the U.N. Security Council, which led to unusually harsh statements from US and Russian officials. Moscow accused Washington not only of criminal negligence but also of supporting ISIS. The Assad regime, eager to build on this conspiracy theory, echoed the charge.

Moscow and Damascus have treated this incident as effective permission to ignore their commitments under the cease-fire agreement. Mr. Kerry has said that Syrian forces were “evidently” responsible for the strikes that hit the U.N. aid convoy west of Aleppo on Monday. The Assad regime had already struck Aleppo on Sunday.

Of all the parties to the cease-fire deal, the only one showing any urgency toward changing the status quo is the U.S.

The U.S. had made errors in military strikes before, and the Syrian battlefield remains messy and complex: Had the cease-fire held, the next step would have been joint U.S.-Russian targeting of ISIS fighters and groups aligned with the al Qaeda affiliate formerly known as the Nusra Front (now Fatah al-Sham). Mixed among the radical Islamists are rebels of a less extreme orientation. These groups have been warned but may not separate themselves from Fatah al Sham because they view it as an effective military ally against the Assad regime. Russia’s history of disregard for civilian casualties means that the U.S.–now linked to joint military operations with Moscow–would bear responsibility and blame for the deaths of non-combatants.

Mr. Putin has invested heavily in fortifying the Assad regime and projecting military power in Syria. His success has left President Barack Obama little choice but to move toward Russia’s position–shifting U.S. focus away from aggressive steps to remove Mr. Assad from power and toward possible joint military action against a common enemy, Islamist extremists–if Washington is to succeed at reducing the violence in Syria. Mr. Obama needs Russia, and its resources in Syria, on board to stabilize Syria even somewhat before the end of his presidency. But Mr. Putin’s refusal to restrain Mr. Assad and Russia’s combative attacks show that he doesn’t feel that he needs Mr. Obama, Miller said.