stroller angst

So recently Ranger has taken to having stroller angst. As in, he is perfectly content and quiet until you put him in the stroller. The moment he feels his little tush brush against the seat, he protests and loudly. At first I thought he must be (tired/hungry/hot/cold/dirty) but having eliminated these possibilities before leaving the house, I began to wonder. Then I tested another variable: does he continue to cry after being taken out?
In short, no.

I can usually get a good five blocks or so before I can't take it any more (neither the screaming or the looks of people passing by) and I take him out. I'm sure it looks weird, me pushing an empty stroller and carrying an increasingly heavy baby. (and if you happen to know what on earth could be causing this and more importantly have a suggested solution I would so very greatly appreciate it, and so would all the folks living within a five block radius).

So today my mother in law and I were walking back from lunch, with Ranger screaming as though we were pulling out his toenails via his tonsils. I was resolved to ignore him, and so focused instead on the fact that there were several folks wearing Army shirts ahead of us. As I looked, I saw that they were all projecting that "look" of military - I can't explain it, but there is a "look" that many military have about them. As we passed them, I said to Ranger - If you don't stop crying, I'm going to call President Obama and have him draft you into the Army.
I heard a few chuckles before we were out of hearing range.

Shortly there after my mother in law's will broke and she picked Ranger up. His cries stopped instantly- not even a whimper left.