Despite repeated setbacks on the path to peace in war-wracked Syria, the United States and Russia will give diplomacy another chance, as Washington convenes international talks in Europe this weekend to try to secure a ceasefire that sticks. Washington and Moscow, which officially cut off bilateral contact on the issue last week after a truce deal unraveled, yesterday announced two days of talks — in Lausanne on Saturday, and in London on Sunday. The meetings come after Syria was plunged into some of the worst violence it has seen, as government forces backed by Russian airpower push a brutal assault on rebel-held eastern Aleppo.