Because when the secret programs are finally revealed in these investigations, if the Democrats do what the administration Republican strategists expect they will do, Republicans will be able to claim that it was the Democrats who forced the end of these essential anti-terror spy programs.
It's good strategy too providing two things:
1. That the Democrats will appear to successfully force the administration to reveal these secrets.
2. That the majority of the American people believe what the Republican Party thinks they believe, that when it comes to terrorism, security is more important than liberty.
Those are two huge assumptions, but if the Democrats are going to go ahead and pursue this first objective, revealing the illegal nature of Republican administration spy programs, they had better plan ahead for the second objective. They had better have some way to get the American people on their side. If they don't and Republicans successfully do smear the Democrats with this strategy, 2008 could be the comeback year for Republicans.
There can be little doubt that the White House Republican political machine is using these illegal spy powers to snoop on American political dissent, but somebody had better have some rock solid evidence before they break down these walls of secrecy or there will be hell to pay in the years ahead. Republicans may yet succeed in using terrorism to win their perpetual Republican majority.