Wow! Very impressive & Beautiful pictures. Is it common for Coptic Christians in the U.S to have tatoos?
Not so much, but some do. In the 80s and 90s there was a revival of sorts of it in Egypt.
The Copts had their hands branded with a cross when they paid their jizya poll tax when the Muslims came and set up their governance of Egypt, they extracted the jizya, and used to brand your hand to show you paid (it also marked you for lynching). When the muslims stopped doing it, the Copts started, of their own volition, tattoo themselves on the hand with a cross, usually at a pilgrimage (I got mine at Zaytoun, after going to Jerusalem). I remember once buying a kufiyah. While I was looking at it, the shop owner saw my tattoo and asked me if I was Christian. When I replied yes, it told me "half price."
A Copt showing me his Cross pointed out "the muslims here, some are from Saudi Arabia. They are a foreigner here. Some their grandfather was Copt but converted. They belong here, but they are weak. My grandfather and his grandfather [pointing to the Cross on his own hand] were strong. This is the proof that they were strong. Ever since the time of the Apostles, every generation until today, my ancestors were willing to die for this. I am willing to die for this." Not an empty fear in Egypt nowadays.
Ἐν τούτῳ νίκα
In hoc signo vinces
IN THIS SIGN CONQUER