I can't tell you how it infringes on "responsible gun ownership" but I can tell you why it is a political tool rather than a law-enforcement enhancer...

...as soon as it becomes common place to keep records of gun "fingerprints" it will become just as commonplace to alter them.

We unfortunately live in a day where people are incapable of judging the reality of crime/law enforcement from an exciting episode of CSI.

Just one of those many cases where, again, I think we should be able to hold our own guy's feet to the fire and judge the logic of their rhetoric.