Pelosi herself was instrumental in making the executive branch unaccountable to Congress or to law when she declared impeachment of Bush to be "off the table." This declaration by the speaker of the House has effectively released the Bush Regime from any accountability, just as the Enabling Act released Hitler from any accountability to the Reichstag, the German constitution, or statutory law.
Moreover, the case for impeaching Bush and Cheney -- indeed the entire administration -- is by far the most powerful and necessary case for impeachment that has ever existed. By declaring Bush unimpeachable, Pelosi is giving away Congress’ only remaining power to prevent tyrannical rule by the executive branch. If Bush is above impeachment, every future president will be as well.