Since then, every American president has used military force without a declaration of war. This article will use the term "formal declaration of war" to mean congressional legislation that uses the phrase "declaration of war" in the title.

Who must declare war?

The Constitution grants Congress the sole power to declare war. Congress has declared war on 11 occasions, including its first declaration of war with Great Britain in 1812.

What does war without declaration mean?

An undeclared war is a military conflict between two or more nations without either side issuing a formal declaration of war. The term is sometimes used to include any disagreement or conflict fought about without an official declaration.