That's a complete crock.
The liberal media made every effort to question, challenge, and criticize Bush's proposals to force Iraq to comply with UN resolutions or face military action. They were sure to load up their "discussion panels" and "guests" with Clintonistas and other left-wingers on every news-cast for 9 months - Summer of 2002 through March of 2003. It was a daily barrage of thinly-veiled contradictory bias from the left. The typical fare.
And that leads me to the liberal lie that has become their mantra of late - the so called "rush to war". We farted around for 9 months, trying to work with the inept and impotent UN, giving Iraq plenty of time to hide, export or dispose of their weapons as well as prepare for a war. If anything we waited too long.