WASHINGTON — Though federal shutdowns have become a depressingly familiar ritual of American politics, the current one was born of a newer, more toxic dynamic – one in which the old partisan arguments about the size and role of government have been supplanted by a tribal battle over what it means to be an American. The tactics are the same, and in some ways the culmination of a no-compromise, winner-take-all approach that has been taking root since at least as far back as the rise of the tea party movement.