Certain areas of the level have this issue and some don't, so I was able to learn (as a player) where I should be and engaged with this as a gameplay design. My high scores aren't amazing though, but it was an interesting ego story about how these enemies probably wouldn't give me a warning prior to warping in and just want to win the war. Jon Hare would be impressed with this idea, and I know that because he was an old family friend prior to forming Sensible Sensible and making Cannon Fodder.
So long as the player has some form of winning against the enemy, and you aren't just being mean, I class it as a valid war game.