Without permission from Congress, states cannot make agreements with whom?

States cannot make agreements with foreign countries without the permission of Congress because the U.S. Constitution explicitly grants the federal government the power to manage foreign relations. Article I, Section 10 of the Constitution restricts states from entering into treaties, alliances, or confederations with foreign nations. This is to ensure a uniform national policy in foreign affairs and to prevent individual states from engaging in actions that could undermine or conflict with national interests.

In contrast, states are allowed to enter into agreements with each other, often referred to as compacts, as long as they have the consent of Congress when necessary. Agreements with tribes are also permitted, but like state-to-state compacts, these may also be subject to federal oversight depending on the context. Thus, agreement with foreign countries is the primary area where state actions are expressly limited by the Constitution to maintain a cohesive national strategy.