Bush is now proudly, openly, brazenly a pro-torture leader:
To support Bush's veto, you essentially have to reach two conclusions. First, you must think torture is morally and legally acceptable in prescribed circumstances. Assuming you do, though, that's not enough. It's necessary but not sufficient. To support Bush's position, you must also think that the federal government is capable of exercising this awesome power in a responsible way. I've heard a lot of arguments justifying Conclusion #1, but virtually nothing to justify Conclusion #2 (other than "trust us"). Indeed, most of the arguments we hear from the pro-torture side ticking time bombs, evilness are only relevant to the former.
There was a time when conservatives were leery of handing the executive unchecked power to use against individuals it could both seize and detain indefinitely. Some conservatives maintain that skepticism toward government power. The rest ... well, they're Republicans.