Yes we did, then we turned around and gave Mexico $5,000,000 to compensate them for the territories we won fair and square. Treaty of Guadelupe.
My third great grandfather fought, and was captured, in that war. His father (US AG John Jay Crittenden) brokered a prisoner swap to save him.
Excellent post... I am too tired to respond adequately...I will tomorrow, but it sounds like you have some real heroes in your family!
:)
Julie