Israel is free to have Jerusalem as their national capital, at this point.
The Democratic and Republican Parties have laid the issue to rest, and in the end, what the United States does is final with respect to Israel. Both parties are now on record as supporting Israel's claim to the city of Jerusalem, and this is a big victory for Israeli nationalists.
It isn't any more acceptable than having China annex Tibet, but nobody is seriously going to stop China anymore than anybody is willing to stop the United States on this matter.
Israel's leaders are free to take all of Jerusalem at this point or at least begin to cover over East Jerusalem in illegal colonial settlements, but if they're smart, they'll leave the eastern portion to Palestinians.
If they are not, then they condemn Israel to eternal struggle and strife. There will be no peace, and there will be no two-state solution. No Palestinian leader will accept a nation without Jerusalem, but as we see, none of the two major parties inside the United States really cares.