Arthur Silber says war is always a choice and the decision is always based on politics, not "intelligence." It's clear that war with Iran is unnecessary, even if they do get nukes. Iran has pointed out that countries without nukes are invaded by the US and countries with nukes are not, so it seems entirely sane for them to pursue nukes--whether or not they are doing so now. Also, they have no desire to be The Country Formerly Known As Iran And Currently Known As A Sheet Of Nuclear-Blast Glass, which is what would happen if they actually obtained and used a nuke.
Megan McArdle seems to be dialing down the stupidity a little of late. (She'd have a hard time increasing the stupidity from her current level and it's something she should have thought about a very long time ago.) But don't worry, she's still Our Megan.
I'm not sure we can fix this problem without knowing the answer to the question we've been asking for a year now: why did the ratings agencies underestimate the tail risk, and is that reason fixable?
For money. That is rather obvious.