He needs to make the walkout a short one or risk permanent damage to Chicago’s reputation as a business center and to the reputation he has carefully crafted as mayor of a city on the come finally confronting its formidable challenges.

But he can’t step in, as Chicago mayors often do during labor strife, because there is so much bad blood between himself and Chicago Teachers Union President Karen Lewis.

He needs to appease a CTU he has alienated by his strong-arm tactics. But he cannot afford to cave after criticizing his predecessor for doing just that, nor does Emanuel have the money to buy labor peace after draining the last penny of CPS reserves with a $1 billion shortfall in next year’s school budget.

That’s the situation that confronts the former White House chief of staff after Day One of a strike that everybody saw coming but nobody could quite figure out how to avoid.