Fighting an interplanetary war longer than humanity had even been civilized, and all over nothing.

Commander Norton did not want to be remembered by history as the man who started the first interplanetary war.

Anton's machines were long out of date, and none had been developed even for interplanetary war.

"Can't let you get in the middle of an interplanetary war all by yourself."

There hadn't been an interplanetary war yet, but perhaps the time was ripe.

Mars played a significant role in each of the three major interplanetary wars.

An interplanetary war is not a long drawn out struggle.

Or would you like the next contact to take the form of a rip-roaring interplanetary war?

If you do this, I am pretty sure you'll be considered an invader and would start an interplanetary war.

At the start of the 21st century, an interplanetary war broke out.