On Brexit, the EU isn’t strong enough to be weak right now

London (CNN)When Donald Tusk, President of the EU Council, tweeted on Wednesday that there was a “special place in hell” for those who promoted Brexit without a plan, the reaction from certain corners of London was furious. Europe has endured a near-unprecedented migration crisis. The euro area is still recovering from the aftermath of the global financial crisis — which hit Greece so hard it needed the largest bailout in history. It is coping with populist movements becoming increasingly powerful in national elections, forcing mainstream politicians to ape once-fringe political ideas. It has among its ranks countries like Poland and Hungary openly undermining the rule of law. And it is looking at Rome, wondering if — maybe when — Italy’s …