mark_b:

My question doesn’t ask “how much the cost.” It assumes that the cost are known. Knowing the costs, would they undertake the action? What is the cost they are willing to incur? Also please assume that we are starting from zero, ie the invasion of Iraq has not yet occurred and ITS costs have not been incurred. Merely inquiring what they would be willing to tolerate for the benefit of having an Iran that is nuclear weapon free and consensually governed and a nominal ally?