Unilateral sanctions, a foreign policy tool of powers like the U.S. and EU, target countries such as Iran, Cuba, and Venezuela to exert political and economic pressure. This article examines their legal, political, and ethical legitimacy through international law, humanitarian impacts, and ethical perspectives. Using frameworks like the UN Charter and the International Covenant on Economic, Social and Cultural Rights, and analyzing case studies (Cuba, Iran, Venezuela), the research shows that unilateral sanctions often lack legal legitimacy and, by causing widespread civilian suffering, constitute "economic terrorism." Instead of altering government behavior, they violate human rights, including access to food and medicine. For instance, post-2018 JCPOA sanctions on Iran led to shortages of critical medicines, while in Venezuela, they triggered 7 million migrations. The article evaluates arguments from supporters and critics, proposes criteria for identifying economic terrorism, and suggests solutions like drafting a treaty to ban unilateral sanctions, enhancing humanitarian exemptions, and promoting regional cooperation. Ultimately, it calls for reevaluating unilateral sanctions and prioritizing human rights in international policymaking