NEED SOME HELP ON A CONFUSING SCENE..

I have watched this film probably 200 times, and I have yet to fully understand a few things, particularly one scene..

Could somebody explain this in a "simple way"?

I do not understand the premise of the entire "abort the operation" scene. Yes, I realize, the original mission wasn't supposed to include Rambo engaging the enemy. But, why did Murdoc simply order him just left there AFTER he sent a helicopter crew with Trautmann to go and search for him?

This can also lead back to the original idea of - why even have the mission to begin with in the first place?

I just didn't understand the scene - also didn't understand that one guy's smug attitude (with the sunglasses - the guy who then says "you aren't going anywhere"). From the moment Rambo walked in, the guy had this arrogant attitude against Rambo, with his dirty looks and not even getting him a drink.

I also never understood what he meant by "no...your men...don't be a hero!" when Trautman was yelling "you goddamned mercenaries..there's men down there, our men!!


Can somebody simply explain this all to me? I am sure politics are involved someway, but it was like - okay - why have a mission if you were just going to abandon the guy you sent over to partake in the mission?