The whole foundation of the art is based on a contradiction...what is a martial art that is 'not an art to fight enemies with'?
Personally, I use the phrase "martial art" pretty loosely. Technically speaking, i'd describe Aikido as a "pax art." There is a huge overlap between the two concepts, but to me the difference seems to fix the paradox you describe. It's not an art to fight enemies with: it's an art of reconciliation with people.