A little Constitutional law for all the non-US citizens (the US people should already have known this).

The only justifications for impeachment under the US Constitution are "treason, bribery, or other high crimes and misdemeanors". Being mistaken about Intelligence information does not rise to this standard.

In Clinton's case, he clearly lied under oath, which is a felony (which can be considered one of those "high crimes"). Ultimately, the trial by the Senate needed to remove from office is a political affair, and there was no stomach for it amongst the electorate. So he stayed.

While there may be the "stomach for it" politically now as applied to Bush, there is no basis on which to bring such an action. Also, the Democrat's hold on both houses of Congress is relatively thin. It will never happen.