iraq was stupid because it was obvious that it wasn't going to work, not because it infringed on some moral principle. from a purely moral perspective, iraq should have been obliterated, and there remain a number of countries in the region that ought to collapse or be collapsed. it just had no chance of success because iraq is a deeply conservative society that wanted more religion and not less of it.
there's a good chance that this might work in iran and if it does work in iran it should be repeated in other states that it would have a high likelihood of success in, although there are few of them. iran is actually almost unique in that sense.
if the guardian claims that revulsion with the iranian regime is not a justification for force, i disagree. some level of tolerance for people different than you is perhaps required in this world, but slaughtering tens of thousands of your own civilians is not something that can or should be tolerated.
the international order needs to be reformed to ensure that states that act like iran are held accountable by it.