It was back in the mid-90s when I was working from home and I got a call from our clinic defense phone-tree.
Our point person had received an emergency call from a local non-profit full reproductive services women's health clinic. A man in a car with tinted windows was parked in a lot across the street from and facing the clinic. The clinic doctor was due to arrive very soon. The local police had been called by the clinic, but did not consider the situation an emergency.
I called the next five women on the phone tree, and then jumped into my car, heading for the clinic.
When I arrived the car facing the clinic was still there. A dozen women were standing with linked arms in front of the clinic. Other women were arriving.
We linked arms facing the unknown car. After about ten minutes or so our clinic doctor arrived. He was a good man, a strong man. But he annoyed the hell out of me because he had a vanity "doc" license tag.
We women moved like a gate to admit the doctor into his private space in front of the clinic. Then we reestablished our linked arms barrier.
The man in the car with the tinted windows (and the many anti-choice stickers on his bumpers) slowly backed up and drove away.
We were very glad he did not shoot at us.