Mr Obama and Republican leaders spoke of co-operation on trade and taxes the day after the election. But they do not trust each other. And Republicans are far from united. Mitch McConnell, the new Senate leader, could be stymied by a handful of conservatives led by Ted Cruz of Texas. They may insist that any budget bill must end Obamacare (though Mr Cruz has said he might settle for repealing bits of it), or refuse to raise the statutory debt limit, raising the spectre of arbitrary cuts to federal payments or default on the national debt. Republicans must avoid such calamities to prove they can govern. Otherwise, as their majority leader in the House, Kevin McCarthy, predicts, “There won’t be a Republican president in 2016.”