Above: the advertisement that drove US nationalists into a frenzy.
And here is the lie that killed thousands and changed history:
“Mexico has passed the boundary of the United States, has invaded our territory and shed American blood upon the American soil.” — Pres. James Polk May 11, 1846
As Sen. Abraham Lincoln noted some time later, “The whole of this,–issue and evidence–is, from beginning to end, the sheerest deception.”