Veteran's Administration refuses to allow veterans to vote

Why won't the Secretary of the Veteran's Administration allow veteran's in his care to register to vote? From the New York Times

On May 5, the department led by James B. Peake issued a directive that bans nonpartisan voter registration drives at federally financed nursing homes, rehabilitation centers and shelters for homeless veterans. As a result, too many of our most patriotic American citizens — our injured and ill military veterans — may not be able to vote this November.

These are the guys who fought for our right to vote, and now the VA won't allow them to register to vote unless they are physically capable of escaping control of the Veteran's Administration.

This is more Republican voter suppression, but I thought that veterans were a Republican-oriented voter block? What are Karl Rove's disciples afraid of? Poor veterans?