During the course of a National Review article on the likelihood — or lack thereof — of Social Security reform in a Donald Trump presidential administration, Andrew Biggs offers a succinct description of the problem.

The simple point is that Social Security has promised more in benefits than it will collect in taxes. Politicians have know that fact since the late 1980s and have failed to act. It is true, as Trump points out, that Americans have paid into Social Security all their lives. But they simply haven’t paid enough to cover what they expect to receive back in retirement benefits. That doesn’t mean we should pull the rug out from under retirees who have few options available to them. Trump is right that someone who has paid into the system for his entire life should not suddenly face large benefit cuts. But younger workers haven’t paid in all their lives, and they have the option to save more or delay retirement. They should do so. The only other realistic option is for those same workers to pay higher Social Security taxes. Compassionate-sounding arguments don’t make difficult choices go away.