Final answer:
An executive agreement allows the U.S. president to commit to international agreements without Senate approval, unlike treaties which require a two-thirds majority in the Senate. Controversies arise over whether this bypass the constitutionally intended process, exemplified by debates like those over the Iran Nuclear Agreement.
Step-by-step explanation:
An executive agreement is a type of international pact forged by the president of the United States without requiring the formal consent of the Senate, as opposed to a treaty which necessitates a two-thirds vote in the Senate. This allows the president to efficiently conduct foreign relations and address modern policy challenges. However, this practice raises debate about whether it circumvents the intended constitutional process of treaty ratification, exemplified in the controversies over agreements like the Iran Nuclear Agreement.
Congressional executive agreements are another form of international agreements, which are approved by a simple majority in both the House and Senate.
The Supreme Court has upheld that executive agreements are legally equivalent to treaties provided they don't change federal law, as in the case of United States v. Pink (1942).