"Vice President Dick Cheney on Tuesday vigorously defended the Bush administration's use of secret domestic spying and the expansion of presidential powers, saying, 'it's not an accident that we haven't been hit in four years.'"
Note the assertion in this "news" article of an expansion of presidential powers. Perhaps such assertion in the lead sentence of the news story is more commentary than statement. The best I can figure out at this point is there has been no expansion of Presidential powers. It seems most likely to me that Congress was exceeding its Congressional power with its efforts to make FISA relevant to the activities of the President as Commander in Chief. Of course, that's my sense of the debate at this point. Apparently the Supreme Court has not opined in relevant ways to date. That observation alone seems to me to imply that there has been no expansion of Presidential powers. After all, if no clear statement has been made in the past, then the limits of the President's powers must currently be ambiguous in this area of Constitutional interpretation.