When you and your sister did it, it was one thing.  

When  governments do it, with escalation, 'patriotism' results in the deaths of actual people.

That's when we see the 'war hawks' and the 'chicken hawks' and the 'arm chair generals' and the others who want other people to die for their egos.

And the US can't 'run to Mommy' like you did as a child.