In order to ensure our security and continuing stability, the [United States] will be reorganized
    into the first Galactic Empire, for a safe and secure society which I assure you will last for 
    ten thousand years.

Jokes aside, this 2014 article explains much of the rationale for keeping a state of emergency active. It preauthorizes certain actions, including the ability for the president to reorganize the military and appoint additional generals beyond the number set by law for non-emergency situations. Given political climates where Congress can hold up seemingly minor changes as a political tool, it's not unreasonable for the executive branch to maintain flexibility when things can militarily change on the ground with barely any warning. The scoping, however, is vague, and there should certainly be more guidelines and oversight for the state of emergency itself, than there are now.

http://www.usatoday.com/story/news/politics/2014/10/22/presi...

And, for context, we remain in a state of emergency with respect to Iran since the hostage crisis, some 36 years later.

https://www.whitehouse.gov/the-press-office/2016/03/09/notic...