And it wasn't just to beat the traffic home.
"Congressman Shimkus was frustrated that the president was not offering any new ground and left with just minutes remaining in the speech,'' his spokesman said.
You'd never know it, but Shimkus is a West Point graduate and a former high school teacher.
Illinois Rep. Mark Kirk - and candidate for Obama's old U.S. Senate seat - committed a lesser but still annoying offense: He whined. Disingenuously.
"He talked at us instead of talking with us," Kirk complained.
Um, it was a speech, not a meeting.
He was talking to you. And to America.
"I hoped he would set aside the public option and that he would talk about a significant lawsuit reform," Kirk added.
I don't know what speech Kirk was at, but Obama pretty much did that.
Of course, the other side stuck to their scripts too.
Sen. Dick Durbin called the speech "specific."
Really? Which parts? The details on how his plan would be paid for besides rooting out the waste and abuse that every politician promises when they don't have a way to pay for their plan?
Or the part where he backed off the public option but in a way that left some analysts thinking he did no such thing?
Bipartisanship requires abandoning artificial political positions and getting down to the work at hand. So far the only bipartisanship we've seen - and this includes the White House - is an agreement by both sides to retreat to their familiar corners and come out fighting like schoolchildren.
And that leaves the bulk of Americans wanting to walk out in frustration while yelling "You lie!" to the lot of them.
Steve Rhodes is the proprietor of The Beachwood Reporter, a Chicago-centric news and culture review.