With the bombing of the UN aid convoy in Syria and fresh attacks on Aleppo after the Assad regime declared the ceasefire over, American and UN officials are in need of a Plan B. Now that trust between the U.S. and Russia is at a new low after Russia allegedly carried out the convoy attack, the situation on the ground Thas gotten even more grim. With the U.S.-Russian ceasefire accord in tatters, the time has come to put a Safe Zone in place for refugees.

In fact, a de facto safe zone is already in place in northern Syria. The Turkish military’s recent thrust over the shared border has begun to allow Syrian refugees to cross back over into Jarabulus. For weeks Turkey has been advocating that the U.S. and western allies work with it to install a formal Safe Zone. With no other realistic options remaining, this novel development has the potential to be a game changer.

The only viable option is to install a Safe Zone in northern Syria stretching north from Aleppo to the Turkish border and east to just west of Kobani.  The viability of the zone rests on Turkey’s ability to lead the effort and militarily guard the zone on the ground, and the fact that the Syrian regime does not at present fly in this area. The security and humanitarian reasons are compelling, from turning around refugee flight to establishing a sizable zone of stability and allowing the focus to be on eradicating ISIS with Turkey fully engaged.

Ironically, only after the failed coup attempt has President Erdogan gained full control of Turkey’s military for the first time. The controversial aftermath nonetheless has newly emboldened Turkey. At first, this complicated matters while Turkey was successfully pushing the Kurdish YPG forces back east beyond the Euphrates, for western allies have relied on the Kurds as the most effective anti-ISIS force on the ground.

But now that Turkey feels it has successfully created a wedge in the efforts of the Kurds to occupy the ground in northern Syria from west to east, it is focusing squarely on ISIS. In fact, Erdogan suggested to President Obama that Turkey work with the U.S. and others to kick ISIS out of its Raqqa stronghold. And it strongly favors installation of a Safe Zone in Syria.

Importantly, the mini détente between Turkey and Russia helps, because this will dent Russian opposition. Syrian opposition fighters should not be allowed in the zone—only refugees—for otherwise Syria and its Russian backer would view it as a security threat.

Because Obama floated the joint operation against ISIS idea to Erdogan increases the likelihood that with Turkey agreeing to this, the U.S. is more likely at long last to agree on a Safe Zone—which would be a complement to a ceasefire were it to get revived. With a Safe Zone in place and Turkey fully engaged, Western and Gulf allies could turn to dealing ISIS its greatest defeat to date. Kicking ISIS out of Raqqa would lend substantial momentum to the diplomatic track and put much more pressure on Assad to compromise than is currently in place.

The Safe Zone on the ground should be complemented by a No Fly Zone (NFZ) in the air. This would ideally be air policed by Turkey and NATO, and with Turkish troops guarding it on the ground, either the UN or the EU could run the Safe Zone. With NATO engaged, neither Russia nor Syria will risk attacking the zone. Back home in the U.S., the Obama Administration would get support from this from both Hillary Clinton and Donald Trump who both have called for installing one.

In fact multiple short term safe zones have already come and gone in this conflict, each small in scale in western Syria and usually agreed between Hezbollah and Syrian opposition forces. None of them were bombed by either the regime or Russia.

Concern about Russian opposition to a Safe/NFZ Zone is overblown, for after bombing the UN humanitarian convoy and trashing the ceasefire it helped broker demonstrates once and for all Russia’s true intentions. It is time to seize back the initiative from Moscow. The diplomatic track is dead; from this point the only thing that matters in Syria is dynamics on the ground.

Turkey is the key to what would be a deft move to retake the initiative. Turkey is now aimed at ISIS, having sealed its border, cut off ISIS supply routes, created a de facto safe zone already allowing marked refugee return, and now advocating a safe zone for which it will do the heavy lifting.

The Kurds have been the loser in Turkey’s intervention, and they are unhappy the U.S. allowed Turkey to not only take territory they had taken but also engage them militarily for a brief period. Thus, the U.S. could usefully begin to arm the Kurds more heavily, albeit still indirectly through the Syrian Arab force that Turkey looks the other way on.

There is also an outside chance that the U.S. can pull of a diplomatic coup by getting both Turkey and the Kurdish forces to work with western allies in removing ISIS from Raqqa. It will not be easy, but it is worth a try. Without western troops, and without either the Kurds or the Turks, a military victory there will not be possible–even with western air power fully engaged.

In a conflict that has killed half a million Syrians and seen over half of the country’s population depart as refugees—with another half a million trapped in Aleppo and several other locations—a Safe Zone will help ease this mass suffering, seemingly a good enough reason for installing one.

Moreover in strategic terms, the shift from Turkey makes moving in this direction sensible, as there are zero options otherwise for engendering a chain of events that could get this civil qua regional war anywhere close to a viable endgame.