I prefer to look at it from a scientific view. There is a lot of new research out there. The article MT referenced is one of many that show evidence of the negative effects porn has on men and their relationships. If something affects my marriage negatively, yes, I am concerned.
Up till now I think porn has been more of a religious/moral issue -- but now that there are actual scientific studies being done, I think it deserves our attention.
Many men seem to think it is harmless, and that "all guys do it." True River, I think you're truly a stand-up guy.
Maybe most human beings are tempted, but that doesn't mean they all succumb. People engage in all kinds of activities that may become habitual/addictive. At least it's worth looking into, to educate ourselves about the dangers.