May be struggling to make money but less than 3% military traffic. According to the links below approx. 21k flights in 2014 and 550 of those carried US troops and/or weapons.

See: https://www.iaa.ie/docs/default-source/publications/annual-r... http://clareherald.com/2015/09/272-flights-allowed-carry-mun...

I stopped in Shannon a couple of times, once en route to Iraq and the other on another tour en route back.