[Cboldt]

-- How do a state currently handle heterosexual marriages (also known as marriages) from other states which are illegal within its borders? --

They recognize the marriage as valid. Full faith and credit applies (Article IV).

[DaveyB]

Full faith and credit applies (Article IV).

But if one state bans homo-marriage doesn't the same principle apply that all states must ban?

[riverdawg]

“How do a state currently handle heterosexual marriages (also known as marriages) from other states which are illegal within its borders? —”

“They recognize the marriage as valid. Full faith and credit applies (Article IV).”

I don't think that is true in all states, at least in the case of first-cousin marriages.