I say ACA, Obamacare is politically charged. And the cases you've mentioned all shorten a long name into a colloquial name. This is not the case for Department

I say ACA, Obamacare is politically charged. And the cases you've mentioned all shorten a long name into a colloquial name. This is not the case for Department of War/Defense. That said, let's call it what it is... it's a war machine. Just as we should refer to Israeli Occupation Forces and not "Defense" forces, since genocidal occupation is just about the furthest thing from defense.