Mark, that’s an interesting provision you mention in the defense-funding bill, preventing current and former members of “extremist groups” from enlisting in the military. For one thing it might be unconstitutional, since “advocating discrimination based on race, sex, creed, religion or national origin,” even if “extremist,” is clearly protected speech under the First Amendment. Protections for free speech and association are relaxed somewhat for public employees (especially in the military context), but the government would still need to show that the targeting of service members’ past expressive/associational activity is justified by a viewpoint-neutral state interest (i.e., ensuring unit cohesion, or some other military purpose). Even if open bigotry is disruptive within the military ranks, it’s doubtful that this concern would apply so broadly — to former members of borderline discriminatory groups, for example. So the ban is probably too sweeping.
On the other hand: Maybe this provision would pressure the Democratic party to stop advocating racial preferences?