AMERICA is withdrawing. The threat from Russia is mounting. Ukraine is on the defensive. Despite pledges of new spending, arms production remains too low for comfort. Fear not, Europeans. Recep Tayyip Erdogan has your back. “It has become clear once again”, Turkey’s president and Europe’s prospective saviour said on April 11th, “that European security is unthinkable without Turkey.” Mr Erdogan is often given to bombast, and to casting Turkey as a dynamic regional power, with Europe as an anaemic has-been, so you could be forgiven for not buying his line wholesale. Besides, Turkey’s economy is in a deep funk, and for a country widely seen as a military behemoth, the $24bn (or 2.1% of GDP) Turkey shelled out on defence last year was only a quarter of Germany’s spending. Even so, Turkey’s strongman is not too far off the mark. On security co-operation, rearmament and Ukraine, Europe needs Turkey’s help more than ever.