Platoon has genre WarWar has examples: We Were SoldiersWe Were Soldiers has genre War
[Human]: I like the movie Platoon. Have anything to suggest like this movie? [Assistant]: Are you a fan of War movies and Dramatic movies? [Human]: I am. I also like We Were Soldiers and War Horse. Do you have any thing to suggest similar to those? 
Yes Das Boot and The Big Parade are similar movies.