Mankiw: why do liberals oppose privatization?

Via Real Clear Politics, a link to a must-read article by Gregory Mankiw from a couple of days ago in The New Republic.

I am perfectly happy with Harvard's retirement plan. I have the sense that my colleagues at Harvard are happy with it as well, as are millions of other workers who have similar arrangements. This raises the question: If the liberal Harvard faculty is content with the defined-contribution structure for their private retirement income, why are liberals in Congress (and the liberal New Republic, for that matter) so appalled that Bush would propose moving the public retirement system in the same direction?

As far as I can tell, there are three reasons. The first is that the president proposed it, and some Democrats will oppose anything he advances....

The second reason the left hates personal accounts is that, over the long term, they could destroy one of its favorite battle cries: the alleged conflict between evil capitalists and oppressed workers....

The third reason for the left's opposition to personal accounts is simple paternalism....

Of course, when Democrats speak publicly, they are rarely this frank. They will not readily admit to political opportunism, to opposing the spread of stock ownership, or to distrusting the public with its own money. So, instead, they raise two canards--one involving the deficit, the other involving risk.

Please read the rest of this truly great article. Mankiw nails it, and what's more, the three reasons are pretty accurate psychoanalysis of a certain Princeton economics professor.