Can't say that he was swayed by any pressure or caved. He just thought after 5 years it was the right thing to do.
I listened to Laura Ingraham this a.m. and she said Bush showed a lot of guts just by showing up...It wasn't my favorite speech, but once again it was vintage Bush. He really does try to reach out even when he gets swatted. It's an example of the President doing what he thinks is right whether folks (including us sometimes) agree with him or not.