Navy corpsmen are actually really respected by Marines. They train with them, deploy with them, and a lot of them end up bonding more with Marines than with the Navy itself. There's definitely "rivalry" and talking shit between branches, but when it comes to combat and saving lives, that stuff usually goes out the window. Most Marines will tell you they'd trust a good corpsman with their life.Not having a medic branch makes it look like they see marines as expendable and not worth treating their injures. That's pretty fucked. Especially with rivalry.