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.

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