Declare what? If it's "war" you mean... the answer is Congress...
The President
The Congress
The specific power granted exclusively to the federal government and not to state governments is the authority to declare war.
Congress has the power to declare war.
The power to declare war is a power that belongs to Congress.
The legislative branch has been granted the power of enacting legislation, the complete and plenary power of taxation, the power to declare war, and power to promote the general welfare. The executive branch consists of mainly the president who has been granted the power to veto or sign into law legislation written by Congress; and the judicial branch has the power to decide the constitutionality of legislation.
Congress has the power to declare war not the President.
In the United States, only Congress has the power to declare war. This authority is granted by the Constitution to ensure that the decision to go to war is a deliberate and collective one.
One Constitutional power specifically delegated to the federal government is the power to declare war.
Each state does not have the power to declare war. Only Congress can declare war.
Congress has the power to declare war. The president of the United States is the commander of the military but cannot declare war without Congress.
The power to manufacture money and declare war is given to congress.
The power of congress to declare war and raise an army or navy is an expressed power.