It is in the interests of ALL permanent members of the UN Security Council to prevent this scenario ...... not just the US and European members.
Whether or not Russia and China have any brains or brawn (either will do) on this front remains to be seen.
From China's perspective a betrayal of a neo-Communist revolution to further the interests of openly anti-China fascists within Turkey and the Khamenei's mullahs should be an issue. The New Silk Road initiative needs an EU to link to and should not be wholly dependent upon Iran's continued support.
Russia is in a similar position to China and would do well to keep a lid on the neo-Ottoman agenda.
Although Russian, Chinese, US and European interests align on this front, I'm not sure that any of them have the gonads or the necessary strategic thinking to place a few peace keepers along Afrin's borders with Turkey. Stupidly they may wait for Turkey to invade first.
Given the HUGE number of ATGMs delivered to the SDF by Trump, Turkish losses will be VERY high in Afrin or Manbij. Turkey may rule the skies in this still hypothetical conflict but they will necessarily have to pit conscripts against a battle hardened YPG militia and multiple Arab tribal militias.
Essentially it is time for the UN Security Council to act.
