The Constitution requires every state to afford good faith and credit to acts of other states. To some extent, uniformity is necessary even in a federation. People should know exactly what to expect when they move to or visit another state.
This is what this act would require. Let’s not be detained by the hypocrisy of liberals opposing federal legislation on gun rights when these are the same people who favor federalizing everything else, whether its warranted or not.
Its that simple!
This is not as applicable as it might seem. The devil is in the details.
http://en.wikipedia.org/wiki/Full_Faith_and_Credit_Clause
“...The duties that states within the United States have to respect the “public acts, records, and judicial proceedings of every other state.”
“According to the Supreme Court, there is a difference between the credit owed to laws (i.e. legislative measures and common law) as compared to the credit owed to judgments. Judgments are generally entitled to greater respect than laws, in other states.”
In practice, states are free to reject all sorts of laws and judicial decisions of other states. In past and currently this included slave and anti-slave laws; miscegenation (mixed race marriage); extradition of those convicted of felonies in other states (though this may now be a federal action, crossing state lines to avoid prosecution or giving testimony in court; recognition of homosexual marriage, etc.
Another point is that right now, one of the things advocated by the 10th Amendment Movement is that the intrastate (within a single state) production and use of firearms and ammunition is not within federal jurisdiction.
But if congress is successful with this law, it essentially federalizes intrastate (several states) authority over gun licensing or lack thereof.
As such, more liberty can be lost in this effort than is gained, and once more power is stripped from the states and given to the federal government.