I'd say "ready" means "ready, willing, and able" to restore and maintain civilized order in Iraq. In my opinion that will have to include putting ALL of the militias out of business.
Preferably, Sadr will die in the process...
Well, "to restore and maintain civilized order" the army [and the population it is drawn from] needs to be civilized first. As a thought experiment, imagine trying to do it with an army of barbarians. Thus, they will be ready when transcivilized [i.e. when they overcome their sectarianism ant tribalism, for starters], and not a millisecond sooner.