In politics perception means everything. Truth and justice is simply not of political benefit, unless the people PERCEIVE it to be true and just. Truth and justice are vital in ethics, but ethics and political success have little to do with each other.
And political success and the ultimate success of ideas or ideals have little to do with each other (see Vaclav Havel or Lech Walesa). Truth is an unstoppable force. The Senate is a barely moving body. I'll take the former (truth) over the latter (political success) any day. If we are in politics for politics sake, we are playing parlor games. If we are in politics for the sake of forming a more excellent nation, then truth means everything. Otherwise, it's just who has the best propaganda.