Just like the word itself, which can mean to permit or to penalise, aspects of sanctions can be contradictory: the intentions behind their use as well as their eventual effects. They are often touted as an obvious and “soft” option to conflict, but this ignores the potential for devastating consequences. The history of sanctions is fraught with lessons for current and future governments. War, not peace The first recorded use of economic sanctions was back in 432 BC in Ancient Greece. It was Pericles, builder of the Acropolis, instigator of modern democracy and Boris Johnson’s personal hero, who issued the Megarian Decree, which blocked Megara from trading in any port within the Delian League. Banned from harbours and market places across the Athenian Empire, the Megarian economy was strangled. The city was isolated and its economy suffered. Starvation killed many. The ban strained a fragile peace. After Megara appealed to Sparta for help, the Peloponnesian War broke out. The repeal of the decree was Sparta's main demand. In this case, sanctions arguably became the trigger for war rather than preventing it. Economic sanctions take many forms and their effects can be mild or severe: an asset freeze imposed on named individuals or companies, or a ban on trade in a limited number of products. More powerful measures have included exclusion of some or all companies from capital markets, a ban on direct investment, or exclusion from international payment systems. On some occasions governments have threatened to sell holdings of a country’s government bonds. It wasn’t until the 19th and 20th centuries that the craze for sanctions really took off. The British government, a huge economic power, discovered a way to manipulate foreign policy objectives without the costs of all–out war. They imposed economic blockades during all their major conflicts, from the Napoleonic War to the Boer War. In the 1920s, the threat of sanctions prevented skirmishes in the Balkans from escalating into war. The more interconnected global economies became, the more effective sanctions became as a punishment or threat. In the 70 years to 1914 trade flows rose from 5% of global GDP to 14%. The League of Nations - founded in 1920 and the forerunner to the United Nations (UN) - played a key role in forging country-based sanctions. Acting as an alliance proved far more effective than acting autonomously. It stopped the targeted country simply transferring its economic activity from its aggressor to a new ally. In the second half of the 20th century, the world witnessed peak sanctions. The World Economic Forum (WEF) estimates that in the 1990s “sanctions regimes were introduced at an average rate of about seven per year”. Unsurprisingly, given their position as leaders of the international rules-based order, it was the Americans who used them most prolifically. The WEF’s data shows that during Bill Clinton’s presidency, “around 40% of the world’s population, or 2.3 billion people, were subject to some form of US sanctions.” And, unsurprisingly, “the great majority of sanctions are imposed by large countries against small countries” explains the WEF.  In addition, since the 1960s, the UN Security Council has established 30 multilateral sanctions regimes; the most successful helped bring an end to the apartheid regimes in South Africa and what is now Zimbabwe. The UN has also imposed sanctions on non-state entities such as al-Qaeda, the Taliban, and, more recently, the so-called Islamic State (Isis). Who are you trying to hurt? A report from consultancy Capital Economics suggested that “the objective [of sanctions] is sometimes to appease a domestic audience by imposing some “token” sanctions which are not costly for the countries implementing them”.  But if a government is trying to make an impact on a foreign regime, what should it consider? Although they are often considered to be “soft” alternatives to conflict, sanctions can have had utterly devastating impacts on innocent people. So what are the lessons from history? Economic sanctions, if implemented on a serious scale, will likely lower GDP and smother economies. They can reduce food supplies, risking the lives of innocent citizens. It’s hard to overstate the consequences. In Afghanistan today, 90% of the population do not have enough to eat. In February, former British Prime Minister Gordon Brown argued: “A liberal world order that puts military and economic sanctions before food is neither liberal nor orderly”. He argued for a relaxation of economic sanctions balanced with a maintenance of political ones.  Fears about such horrors are what led to the introduction of “smart” or “targeted” sanctions at the beginning of this century. Sanctioning specific oligarchs in the case of Russia, for example. Unintended consequences One of the longest-running sanctions regimes is the US-imposed regime against Cuba. Professor Lee Jones of Queen Mary University London, author of Societies Under Siege:...