Congress is currently debating making a law that prevents U.S. citizens who are placed on the no-fly or watch-list from exercising the Second Amendment rights to bear arms; including lawfully purchasing firearms. This is a slippery slope when "Due Process" under our United States Constitution is denied.
In my opinion, as a recent criminal justice degree graduate (last month), I think if this is something the Congress or Obama administration is seriously considering doing; they should be required to have the Solicitor General of the United States, file an emergency petition with the U.S. Supreme Court, asking them to review the constitutionality of this proposal. That would be the prudent first step to take, before Congress passes any laws, and the executive branch enforces that law.