There's a common sentiment these days to the effect that we shouldn't deny Trump the Republican presidential nomination if he's the delegate frontrunner going into the convention, since doing so would upset Trump's supporters too much and would be harmful in other ways. I've addressed some of the problems with that line of reasoning in other threads (here and here). In this post, I want to come at the issue from another angle.
If Trump gets the nomination, he'll lose to Clinton. It's doubtful that Trump will take much responsibility for his loss. He and his most committed supporters will engage in a lot of blame-shifting, conspiracy theories, etc. We can expect them to blame the Republican establishment, the Never Trump movement, and other Republicans for Trump's loss. We'll be told that Republican leaders didn't support Trump as much as they should have, that a lot of Republicans who could and should have voted for Trump didn't do so, and so on. It's likely that many of them will tell us that they're leaving the party, can never trust the Republican establishment again, will respond to the Never Trump movement by not voting for future Republican nominees after Trump, etc.
So, what's the point of accommodating them at the convention in an attempt to avoid having them angry at us? They'd probably eventually get angry at us in a similar way a few months after the convention, even if we were to accommodate them. Many of Trump's supporters have some of the same unfortunate character traits as their leader. These aren't the kind of people we should want to accommodate much. There can be some accommodation, but only up to a point. Giving Trump the nomination just because he had the largest minority percentage of delegates, or because he fell short of a majority by only a small margin, is going too far. The anger we'd avoid at the convention would likely erupt a few months later. Even if that weren't to happen, it wouldn't take much to set some of these people off.
The best way forward, including the best way to grow the party over the long run, is to keep Trump from getting the nomination. The more reasonable and persuadable Trump supporters, along with a lot of other people, would be attracted by a Republican president working with a Republican Congress, especially given how bad the alternative is. We'll attract more people over the long term, including some of Trump's supporters, if a Trump presidency is rejected sooner rather than later.