1. In terms of men; the US Civil War, because Americans were killing Americans.
2. In terms of of ships; WWII.
3. In terms of jets; Vietnam.
I think that the patriots biggest loss was at the battle of Saratoga.
the Revolutionary war
The US Civil War was probably the biggest.
the biggest danger toward the US troops was the disease in Mexico
The biggest loss in a game can be 25-0.
The Vietnam War is considered a loss, because the communists did conquer the country that the US fought to preserve from the communists. There are many others, but the only wars in US history that were declared are The American Revolution, The War of 1812, World War One, and World War Two. But if you count unofficial wars, then there are many where we did not fulfill our goal, Vietnam being the biggest one.
Reconstruction.
Russia
The US got out of the Great Depression and the US became the biggest world power.
a c Milan's biggest loss is accepting Ronaldo
There are only 2 big threats and they are polution and loss of foods. Te biggest one can be said is the loss of food.
Well it depends on what you mean. The civil war was the war that we took the most casualties in but im pretty sure that world war two was the biggest as far as how many people were in it.