Two things to say about the NRA's shocking new advertisement.

First: on the merits, the NRA's idea to place armed guards in every American school is a foolish one. Mass casualty shootings do not happen only in schools, as the phrase "going postal" should remind us. Moreoever, as Steven Strauss has argued, even in schools, armed guards will prove a weak defense in a country where rapid-fire large-capacity weapons are so easily available:

The U.S. has about 100,000 schools, so we're discussing on the order of 150,000 armed guards (some schools would be large enough to warrant several guards), for 75 million students, about 200 days a year. There would be lots of opportunities for deadly incidents: Armed guards misreading student behavior (e.g., a student mistakenly shot while playing with a toy gun); Student fights where a student grabs the guard's gun; A mass shooting scenario where students are killed in crossfire; or, a nightmare scenario where a psychotic guard massacres students.

Second: even if the idea were a good idea, the NRA's sneering references to the president's family are beyond the pale. As the makers of the NRA ad should know, and probably do know, the First Family has come under years of racially coded attack for their "uppityism," as Rush Limbaugh phrased it. This latest attack ad looks to many like only one more attempt to enflame an ancient American wound.

Generally speaking, a president's family should not be subject to political criticism. That rule was honorably upheld in the case of the Bush daughters, who grew into fine young people, and the rule should be same for the Obama daughters - especially if it's true, as has been widely reported, that this first family has faced a unique degree of threat.