The greatest humiliation to the united states in the war of 1812 occurred when the british: sank the leopard just outside territorial waters off virginia.

The most and greatest humiliation to the United States in the war of 1812 occurred when the British invaded and burned Washington, DC. When the British invaded and burned Washington, DC it was the greatest humiliation of the U. S. in the was of 1812. The answer in this question is invaded and burned Washington, DC.