Finally, the blitheness of Krugman's actual solution—a massive tax increase—ignores all the knock-on effects of that idea. Keeping Social Security and Medicare whole will require a tax increase in excess of $1 trillion, which would have massive repercussions on wages, the costs of starting a business, and economic growth in general. It's far from a... See more

Second, he speculates that mortality rates might continue to drop. While that might be good news from an actuarial perspective, it seems both morally horrifying and incredibly risky to base a long-term entitlement program on the assumption that more people will die at a younger age.