As I suspected, this challenge was easily met by all commenters.
It is of course Arilus cristatus, commonly known as the wheel bug for the very structure shown above. I didn’t get a full body shot of this specimen, but here’s a wider view.
Among the largest assassin bugs in North America, they can deliver a painful stab with that beak. I foolishly held one when I was a kid, and I’ll not be making that mistake twice.
For more info, see the species info page at BugGuide.