I think it is more than that. I remember relatively little public opposition to the 1991 Gulf war or the 2001 Afghanistan war. Both were considered 'good' wars where U.S. was unquestionably on the 'right side'.
US Public thinks a good war is a "clean" war
When you attack a legitimate target, when you perform a surgical strike, remember when Norman Schwarzkopf showed us that video of "one lucky Iraqi bastard?"
In contrast to what was broadcast in OIF or OEF, like this
Or to exen some extent the footage we saw (well, I wasn't born then) on TV about Nam
The public doesn't really care why we were there; they expect us to go in, get the job done, regardless of what or why we were over there, and then get out. They don't care (and trust me, I know). As long as you can keep the war clean, you have no problem.
But when you are at ground level, seeing what I have seen in war, it started to resonate with the public, and the public started to think, " Why are these people doing this as if they are doing this themselves? And questions started to pop up, because you immerse yourself in our world when we were fighting over there, instead of playing a game when you saw a bomb hitting a target. After all, you don't feel anything about that (And if you do, you probably need to go see a doctor....)
That's why every time you see footage, like you are immersing yourself in it, this is going to polarise people. Instead, if you show just stuff that needs to be done, as a debrief, then instead of feeling you were there, you felt these people had achieved something.