Iraqi dictator Saddam Hussein attacked Iran causing the Iranian leadership to declare war as well. More countries, especially the United States of America supported Saddam Hussein, however, the Iran people pooled their collective will to overcome Saddam's armed forces.
Only congress can declare war, not even the President has this power.
The USA did not have to declare war on Germany because Adolf Hitler declared war on the USA.
US Civil War & Vietnam War.
1917
Well, in WWII, America was an ally with France so they didn't declare war on France. Although America didn't start war on Italy (one of their enemies in WWII), because America didn't want to join the war. They thought it was too dangerous.
Attack on Pearl Harbor.
Japan. Then Germany declared war on the US.
America declared war after Pearl Harbor, Hawaii was bombed.
Congress declared war on 13 May1846 but by then the war had been going on for three months.
An atomic power can't declare war, that would imply using nukes. The last time the US declared war was in WWII. And nukes didn't exist then.
you declare war