The United States has a longstanding history of imposing and enforcing trade sanctions against Cuba (during his term as president,BarackObamaissued an executive order to restore full diplomatic relations with Cuba; U.S.-Cuba relations have since "chilled" during the Trump administration). Additionally, the United States has imposed trade sanctions against South Africa, and then later against Iraq and Iran. Do these sanctions work; i.e., are they effective, and do they satisfy the purposes for which they are implemented? If so, how? If not, why not, and what should nations be doing instead?