Me. I'll argue that. We could pull out of a number of bases in the Middle East and save a shit ton of money. We could close bases in the US and get the ones remaining back to 100% manning, and increase the morale at the same time (can you imagine if we closed Cannon and relocated all those guys to places like Hurlburt, Ellsworth, hell...even Dyess?)
I'll argue that we've been wasting a ton of money, people, and resources in these never-ending wars in the Middle East. I have no idea what the hell we're still doing in Afghanistan. I have no idea why we thought it was a good idea to execute airstrikes in Libya. I'm still scratching my head at the idea that Syria was worth the first salvo of JASSM in combat.
So...maybe I'm in the minority, but I am absolutely willing to argue the cost of maintaining a world-wide empire, both in terms of military spending and foreign aid.
I'm also willing to argue it isn't an empire. An empire would result in a net gain being returned to the home country. Our model seems to be predicated on paying for everyone else while getting basically no tangible returns out of it.