Our country is standing at a crossroads. Neither the world nor America’s place in it is what it was a generation ago. The unipolar moment is over. And yet, many in the Republican Party seek to claim the mantle of America First while continuing the same failed adventurism of the past. National conservatism as a movement agrees that these people and ideas must be stopped. But we have failed to check their influence in the party largely because we have not offered an alternative that both meet...