I think there are two ways to explain the song.
On the one hand, there is indeed the story of someone who fights in a war. As someone here already explained. But I also see a lot of similarities with another explanation. The song could also be about the fatigue of being famous. It is a constant struggle between the desire to be famous and be loved, and to just live a normal life with family and friends. He does things that go against his own person. He is fighting a war against his own principles he, for this life, sometimes needs to put aside.
I think there are two ways to explain the song. On the one hand, there is indeed the story of someone who fights in a war. As someone here already explained. But I also see a lot of similarities with another explanation. The song could also be about the fatigue of being famous. It is a constant struggle between the desire to be famous and be loved, and to just live a normal life with family and friends. He does things that go against his own person. He is fighting a war against his own principles he, for this life, sometimes needs to put aside.