Guys really do be like that. As soon as something puts us on edge, we start planning how we're going to kick some ass, but if we're with the girl we love, part of our brain is also calculating how long we can keep getting stabbed to buy time for her to run away before we drop dead.
Our entire gender has ridiculous fantasies in all scenarios, such as the ubiquitous "terrorists take over the school, so I have to go all Die Hard on their asses."