I just found out that we can no longer carry circular thread cutters on an airplane.
This is reprinted from the TSA Regulations:
Transporting Knitting Needles & Needlepoint
Traveling with Special Items
Knitting needles are permitted in your carry-on baggage or checked baggage.
Items needed to pursue a Needlepoint project are permitted in your carry-on baggage or checked baggage with the exception of circular thread cutters or any cutter with a blade contained inside which cannot go through the checkpoint and must go in your checked baggage.
Just a heads up.