First of all, "evangelicals are intensely patriotic in a traditional way" is a meaningless statement. Patriotism is not a measurable quantity and there's also no definable distinction (that I can perceive, at least) between traditional and modern patriotism. Secondly, Trump's record on social issues is incredibly imperfect. Enough evangelicals are turned off by Trump's flip-flopping on abortion (never an issue for McCain, and one that Romney headed off at the pass by being strongly identified with his religion) that it's very hard for me to imagine him doing better than Romney among them.
Some evangelicals of course are for Trump (there were plenty of states in the primary where he won pluralities among them, which isn't the case for other groups), but there's a firm group of NeverTrumpies among them that will likely sit the election out or protest vote.
Vosem, the NeverTrump is a dying breed. There aren't any NeverTrump evangelicals, only the establishment types.