Security ... think about it!
Imagine you're visiting Idaho or Arizona. A cop pulls you over and asks to see your driver's license. Then, even though your license is current, he draws his sidearm, cuffs you, and hauls you off to the calaboose. Your crime? You were driving on a Nevada license; you neglected to get a new and separate driver's license, in advance, for each state you're planning to pass through. Ridiculous? Of course it is. Article IV of the Constitution stipulates, "Full faith and credit shall be given in each state to the public acts, records, and judicial proceedings of every other state," and Congress is empowered to make laws describing how "such acts, records and proceedings shall be proved." So if you're married (or divorced) in Nevada, your status remains unchanged when you visit Arizona. The other 49 states also have to honor your license. But in fact, the situation described above is precisely what confronts a law-abiding gun owner who wants to carry his weapon on an interstate trip. Some states honor the "concealed carry permits" of some other states, but not of others. Get out a map, take a few months and a few thousand dollars, send away for the varying requirement to obtain "permits" from seven or eight states -- some of which you may have no intention of visiting -- in order to have a fair chance of being legal wherever you travel (though you can forget New York, California, Washington or Chicago).
