Perhaps the most charitable way to think about this is that the party, as an institution, lacks a functional mechanism for declaring a candidate unacceptable. The party apparatus has been designed to offer support for the nominee, whoever that person is, but not to set standards for its candidates. In some sense this is true of all political parties by definition: Both Republicans and Democrats coalesce around the goal of winning elections, with all other concerns rendered secondary at best.

But Trump’s campaign demonstrates just how far that sort of standards-free backing goes, and how easily it happens. Yes, Trump has been controversial and widely criticized, even within Republican circles: Witness George Will’s call for conservatives to help ensure a 50-state loss for Trump if he wins the nomination.

That call suggests the unusual nature of Trump and his candidate, but it also demonstrates the distinction between party and ideology, and why it is important to distinguish between the two. Will is committed to a political ideology, and interested in the party mainly as a vehicle for that ideology. The party is interested exclusively in its own fortunes, and relies on ideological appeals only when it is convenient. Those who identify more as conservatives than as Republicans have tended to be much more forceful in their opposition to Trump.

Trump, then, is exposing the emptiness of a Republican party which stands for nothing but its own continued electoral success. In this view, there is essentially nothing that he could have said or supported that would have caused the party to withdraw its support. Trump’s campaign has provided plenty of evidence for this; over and over he has said things that appear to go too far—and then paid no political price for it. It is hard to avoid the conclusion that the only way that Trump could have made himself truly unacceptable in the GOP primary would have been to run as a Democrat.