A bone to the evangelicals seems like a weird reason and not particularly likely. But then, I can't think of any reason that is likely, given the body of work from Trump.

I do know this: Jerusalem is the capital of Israel. The Knesset is there. The prime minister resides there, and his offices are there. Ditto the president. The supreme court is there. It is, in all possible ways, the seat of the Israeli government. That makes it the capital. So let's call a spade a spade. Israel's enemies insisting that we call a spade anything but a spade is a way to delegitimize the state of Israel, which is their stated goal.

To me, if there's any harm done to the peace process, it's coming from people making unreasonable demands like "don't call Jerusalem Israel's capital even though it obviously is." Let's base the process on the truth. Then we can more clearly see who is being obstructionist and ridiculous. My prediction is that flags will be burned, demonstrations will be held, anger will be vented (and none of this will be any different from any of the other spluttering displays of rage), and then we'll go right back to where we were before, and then other countries will follow suit and move their embassies too.