Thomas Hobbes had a jaded view of human nature and an even more jaded view of government. He believed that governments were founded for the purposes of self-preservation and that they were maintained by the fear of the citizens.
Hobbes was a proponent of absolute sovereignty in which a singular person is chosen by the citizens to be granted extraordinary executive powers. These include the power to wage war and levy taxes, so Hobbes is in favor of having a popular sovereign control the power to declare war.
He would have approved of a president having the power to declare war once he was chosen by the people.