Bruce Schneier: The Security Threat of Unchecked Presidential Power. Yet another must read, including this explanation of why this not a partisan issue:

This is not a partisan issue between Democrats and Republicans; it’s a president unilaterally overriding the Fourth Amendment, Congress and the Supreme Court. Unchecked presidential power has nothing to do with how much you either love or hate George W. Bush. You have to imagine this power in the hands of the person you most don’t want to see as president, whether it be Dick Cheney or Hillary Rodham Clinton, Michael Moore or Ann Coulter.