I can’t seem to let go of this Chuck Hagel-for-defense-secretary brouhaha. Stop me … but not until I get one more thing off my chest.

Sens. John McCain and Lindsay Graham, both Republicans of Arizona and South Carolina, respectively, have let the cat out of the bag over their fierce resistance to Hagel’s nomination to lead the Pentagon.

Both men have said they’re angry with their fellow Republican for turning his back on his party – their party.

What? When did national defense become a partisan issue? When did the secretary of defense have to toe some party line in order to lead an institution whose leaders insist that the men and women who wear their nation’s military uniform forgo political considerations? These brave heroes take an oath to protect and defend the Constitution without regard to politics. They are bound by that oath to follow “lawful orders” issued by anyone farther up the chain of command than they are – and that includes the civilian commander in chief.

Now it seems that because Hagel, who served two terms as a GOP senator from Nebraska, is being punished by his fellow Republicans because he changed his mind on whether the Iraq War was a noble effort. The new White House chief of staff, Denis McDonough, made a salient point this morning on “Meet the Press.” It is that national security and defense issues belong far beyond the partisan realm.

Another distinguished Republican, U.S. Sen. Arthur Vandenberg of Michigan once offered sage advice that his political descendants should heed as they discuss national defense in the context of overarching foreign policy. He said: “To me, ‘bipartisan foreign policy’ means a mutual effort, under our indispensable, two-party system, to unite our official voice at the water’s edge so that America speaks with one voice to those who would divide and conquer us and the free world.”

Are you listening, Republicans?