Unmasking is not illegal, but it should only be used for the purposes of national security, not political reasons. It should not be done as a matter of routine, which, to me anyway, it seems to have been becoming.
The way I see it, this is in the legal category of "if you don't know it's being done against you, it's not illegal."
Not that I find this rule acceptable, just that I find that is what the rule IS.
Nunes point is there is no SPECIFIC law against 4th amendment violations. There is already a catchall statute, a person whose 4th amendment rights have been violated is entitled to civil damages in what is known as a "1983 action."
Even if there was a criminal penalty, only a fool would think the law would act as a deterrent. All it would do is cause the requester to use something other than boilerplate in unmasking, and I suspect that could be asserted retroactively if a crime was even charged. FISA has a civil penalty clause in it. That clause is there for show. It is not enforceable in court.
What Nunes is doing is selling the lie that the government can be trusted, "see, we made it a crime, so now for sure we won;t use this power wrongly."
That promise was made before. "We are professionals, of course we won't abuse this power." This promise is no different.