The 16 US Federal Intelligence Agencies, already have this information.

They are asking for it now, so that there is a voluntary submission, by each state.

Hawaii has submitted firearms owners, to the ATF.

Hawaii has submitted arrested - convicted - sentenced criminals, to the NCIC.

Hawaii has submitted, many other bits of information, to the Federal Government.

The logic being, if Hawaii has nothing to hide, what seems to be the problem?