Rubble in the Bani Zeid district of Aleppo ©AP/Press Association Images

Boris Johnson rounded on Russia in this week’s parliamentary debate on Syria. The Foreign Secretary backed French calls for Russia to be referred to the International Criminal Court for its bombing campaign in Aleppo. This was a largely symbolic move, much like his encouragement of the protests outside the Russian embassy. But Johnson also struck a realistic tone on the proposal to establish a “no-fly zone” to put an end to the bombing campaign. “We cannot commit to a no-fly zone unless we are prepared to confront and perhaps shoot down planes or helicopters that violate that zone,” said Johnson.

In the same debate, his fellow Conservative Andrew Mitchell, a former international development secretary, argued for a no-fly zone. “No one wants to shoot down a Russian plane,” Mitchell told the BBC, “But what we do say is that the international community has an avowed responsibility to protect and that protection must be exerted. If that means confronting Russian air power defensively… then we should do that.”

The contrasting tones of Mitchell and Johnson illustrate the debates taking place on both sides of the Atlantic. What can the UK, the US and their allies do in the face of Russian intransigence? The answer seems to lie in Washington rather than Whitehall. Some have suggested that Russia must pay a price for its actions. But how? Reports have circulated that the US may drop its opposition to providing rebels with portable surface-to-air missile systems, which would give them the ability to shoot down aircraft. But others point to the risks—these systems could end up in the hands of terrorist groups, or be used to shoot down coalition aircraft also in Syrian airspace. Another option would be a strike on a Syrian regime base as a deterrent against further action. But what then happens if the Russians and the regime respond in kind by carpet-bombing another city?

Escalation is likely to beget counter-escalation. And the US and its allies have illustrated that they are not willing to back strong words with strong action, concluding that this will only make the conflict more violent. A no-fly zone sounds like a benign concept, but it would represent a major escalation. Last month, General Joseph Dunford, Chair of the US Joint Chiefs of Staff, told a congressional panel that to control the airspace would, in effect, require the US to go to war with Russia and Syria. Given the Obama administration’s refusal to establish a no-fly zone prior to Russia’s intervention, it is difficult to imagine that it would do so now that the stakes have been raised.

It appears that finding a means of responding to Russia will be a challenge passed to the next US administration. In the second presidential debate, Hillary Clinton reiterated her support not only for a no-fly zone, but also a “safe zone,” which would require on-the-ground enforcement. The Russians “are not going to come to the negotiating table for a diplomatic resolution unless there is some leverage over them,” she said. Yet reversing Russian leverage will require a significant commitment for a new administration. Aleppo may well be lost by the time the new US president is inaugurated in January. And Clinton has not laid out how such a policy would be implemented. She has, however, ruled out deploying US ground troops, so the question of who would enforce the safe zone remains. While advocates of a no-fly zone argue that it is not too late to establish one, it is difficult to imagine a Clinton administration downing a Russian jet as one of its opening acts.

Johnson’s reluctance to back calls for a no-fly zone consequently seems well-founded. It is likely that the US riposte to Russia will be limited to rhetoric over Syria, and thus the UK’s, too. Accusations of war crimes will make headlines, but they won’t alter the dire pattern of facts on the ground. The options to retaliate to Russia remain flawed, and the US, the UK and their allies show no sign of the commitment necessary to reverse the Russian advantage.

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