Declaring war is a national decision rather than a state. Both will weigh in on the issue considerably but the federal government will have the ultimate say.
The national government declares war.
Each state does not have the power to declare war. Only Congress can declare war.
power to declare war
No. The State Department cannot declare war. The Commander and Chief is the only person who can declare war. That would be the President of the United States.
Congress
declare war and make treaties
yes
A declaration of war is issued by a national government which indicates that a state of war exists between that nation and another. The power to declare war is vested in the legislative branch of the U.S. government under Article 1, Section 8, Clause 11 of the U.S. Constitution..
The power of the national government to declare war is an example of an expressed power. Another example is the power to levy taxes.
Expressed Power
Maine
In both.