JP> Article IV, Section 1 of the United States Constitution states: 
 JP> "Full faith and credit shall be given in each state to the public 
 JP> acts, records, and judicial proceedings of every other State. And the 
 JP> Congress may, by general laws prescribe the manner is which such acts,
 JP> Looks to me like it would be perfectly Constitutional for Congress to 
 JP> pass such a law. And it wouldn't force Texans to obey some 
 JP> Massachusetts law while in Texas. That's a different case entirely. 
ML>  
ML>    I believe that the 10th ammendment  would also come into
ML> play. The  states rights folks would argue, with much merit,
ML> that congress can not  force Ohio to obey a Texas law which
ML> says it is ok for person X to carry a  firearm. The
ML> principle would be Ohio rules Ohio and Texas rules Texas.   
I don't think so.  Look at drivers and marriage
license.  The rules for obtaining these license vary
from state to state but they are honored in ALL states.
Now if the congress tries to set minimum requirements
for the states or says that a TX license holder only
had to follow TX law in CA then the 10th would come
into play.
As long as a TX CCW holder follows CA carry law I would
think it would work.  Imagine if New York City said
that it would no longer honor drivers license issued
from any other state or city the way they do for CCWs.
Heck look at the money they could make by passing a law
and putting a sign at the city limits "$500 FINE FOR
DRIVING WITHOUT A NYC LICENSE.  STRICTLY ENFORCED!".
And then check dl's at all the toll booths.
                      Remember:  Freedom isn't Free!
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