Despite the rising commonality of tattoos, the argument cannot be made that it’s culturally common (in the United States) to be tattooed. This specific point was covered recently by my parish priest and the general gist is that getting a tattoo (or excessive body piercing for that matter) is a violation of the fifth commandment. There are exceptions (Catholics in Ethiopia typically have a cross tattooed on their forehead; sailors who have “sailed the seven seas” get one of their ears pierced) but those exceptions are just that: exceptions. The guiding principle is that our bodies are temples of the Holy Ghost and our outward comportment should be a reflection of our inward disposition. Besides, our bodies belong to God anyway – not us.
As for looking at the "secular norm: " let us not compare ourselves to the heathens around us, but to the Saints in Heaven; we’re going to be judged not according to our relative virtue compared to those around us, but against the absolute standard of the Ten Commandments and the laws of the Church.