This is frightening - because if so, then one way or another, we will have instability in America for a long time. The reason is best explained by Orson Scott Card in the afterword to his book Empire:
Rarely do people set out to start a civil war. Invariably, when such wars break out both sides consider themselves to be the aggrieved ones. Right now in America, even though the Left has control of all the institutions of cultural power and prestige -- universities, movies, literary publishing, mainstream journalism-- as well as the federal courts, they feel themselves oppressed and threatened by traditional religion and conservatism. And even though the Right controls both houses of Congress and the presidency, as well as having ample outlets for their views in nontraditional media and an ever-increasing dominance over American religious and economic life, they feel themselves oppressed and threatened by the cultural dominance of the Left.
And they are threatened, just as they are also threatening, because nobody is willing to accept the simple idea that someone can disagree with their group and still be a decent human being worthy of respect.
Can it lead to war?
Very simply, yes. The moment one group feels itself so aggrieved that it uses either its own weapons or the weapons of the state to "prevent" the other side from bringing about its supposed "evil" designs, then that other side will have no choice but to take up arms against them. Both sides will believe the other to be the instigator.
Could Ambinder be blowing smoke? I hope so. But both Hillary and Obama would have motives to pursue such investigations. Hillary has a vindictive streak that is bigger than the Rocky Mountains.
Obama would probably have to do so in order to placate his political base, especially if he has had to back down from a confrontation with the Joint Chiefs of Staff and General Petraeus over Iraq, a confrontation that would probably torpedo his administration. You thought the 1993 gays in the military controversy was rough?