Illegal drugs refer to narcotic, psychotropic, and related substances whose production, sale, and use are restricted by domestic law and international drug control agreements. Common illegal drugs trafficked internationally include cocaine and heroin, as well as psychotropic substances, such as methamphetamine and ecstasy. Cannabis, or marijuana, is also internationally proscribed. The illegal trade in these drugs represents a lucrative and what at times seems to be an intractable transnational criminal enterprise. According to the U.S. Department of Justice (DOJ), the United States is particularly affected by this criminal activity. Describing the illicit narcotics trade as a "challenging, dynamic threat to the United States," DOJ concluded in 2011 that the drug threat to the United States "will not abate in the near term and may increase." Both cocaine and heroin are plant-derived drugs, cultivated and harvested by farmers in typically low-income countries or in regions of the world with uneven economic development and a history of conflict. The U.S. government monitors drug cultivation and production trends in key countries as part of its efforts to evaluate global trends in drug supply. As of mid-March 2015, data for 2014 and 2013 are partially available. Coca bush, the plant from which cocaine is derived, is mainly cultivated in three South American countries: Colombia, Peru, and Bolivia (see Figure 1 ). Since 1997, Colombia has been the primary source of coca bush cultivation. Colombia's proportion of the global total illegal coca bush cultivation, however, has declined in the past decade—from approximately 77% in 2001 (221,800 total hectares worldwide) to 51% in 2012 (153,500 hectares), according to U.S. estimates. Estimates of harvestable coca bush are used to calculate how much pure cocaine could theoretically be produced each year, taking into consideration the potency of sampled coca leaves, the amount of eradication that took place, and the efficiency of clandestine labs, where the leaves are chemically processed into cocaine. According to U.S. estimates, the global total potential manufacture of pure cocaine in 2012 was approximately 620 metric tons (see Figure 2 ). Cocaine production trends in the past decade, which were dominated by Colombia until 2010, are in flux. In 2012, Colombia ranked second in global cocaine production, behind Peru. This continues a trend begun in 2010, when Peru resumed its top spot in global cocaine production—a position it had lost to Colombia after 1996. The Drug Enforcement Administration (DEA), however, reported in 2014 that the vast majority of cocaine available in the United States continues to be produced in Colombia. Opium poppy, the plant from which opiates such as heroin are derived, is cultivated in Southwest and Southeast Asia, as well as in Latin America (see Figure 3 ). Opium poppy from Latin America, including from Mexico, Colombia, and Guatemala, is cultivated almost exclusively for heroin consumption in the United States. Over the past decade, Afghanistan has risen to prominence as the primary global source of illicit opium poppy cultivation, supplanting Burma, where the majority of opium poppy cultivation took place in the 1990s. Most of Afghanistan's opiates are destined for Europe, Asia, and to a lesser extent Africa. Laos and Pakistan also cultivate opium poppy for the illicit global trade in opiates. Similar to calculations used to measure how much pure cocaine could theoretically be produced each year, estimates of potential production of opium and heroin can be derived from opium poppy crop harvests and other factors. According to U.S. law enforcement data, the threat posed by heroin is increasing in the United States. Heroin availability and demand in the United States are on the rise, due in part to a switch among prescription drug abusers to heroin. Heroin overdose deaths are also increasing in many parts of the United States. Mexican transnational criminal organizations (TCOs) appear to be increasingly involved in heroin production and transportation into the United States. Although Afghanistan dominates global potential opium production (see Figure 4 ), an estimated 4% of heroin available in the United States is sourced from Southwest Asia. Global illegal synthetic drug production is difficult to estimate because it is widespread and production sites can vary significantly in size. In general, the underlying chemicals needed for the production of synthetic drugs such as amphetamine, methamphetamine, and ecstasy may be legally manufactured and internationally exported for legitimate commercial and pharmaceutical purposes. In turn, some portion of the total legal production of these chemicals is clandestinely diverted and misused to manufacture illicit synthetic drugs. Such diverted chemicals typically are processed into illegal synthetic drugs in clandestine laboratories, which can range in size from small residential-sized kitchens to large-scale "superlabs" capable of processing high volumes of synthetic drugs. In recent years, several methamphetamine production labs have been discovered in West Africa, previously known primarily as a transit point for cocaine and heroin. DEA assesses that the majority of methamphetamine available in the United States in 2014 was produced in Mexico. Major trafficking routes connect drug producers with drug consumers, with often sophisticated drug trafficking organizations (DTOs) and transnational criminal organizations (TCOs) controlling various aspects of the supply chain. Significant drug transit pathways flow through Mexico and Central America (for drugs produced in Latin America and destined for the United States), West Africa (for South American cocaine destined for Europe and Afghan heroin en route to Europe and the United States), and all the countries surrounding Afghanistan (heroin destined to Europe, Eurasia, Asia, and Africa). Traffickers employ a wide range of land, air, and maritime methods for transporting illicit narcotics to include go-fast boats, shipping containers, self-propelled semi- and fully submersible vessels, non-commercial aircraft, commercial airlines, global mail delivery services, and private and commercial ground transportation. Globally, the United Nations estimated that in 2012 some 162 million to 324 million people, aged 15 to 64, used illicit substances, including cannabis, at least once in the past year. In recent years, the global cocaine market has been stable, largely due to declines in consumption in the United States over the past decade. UNODC, however, cautions that consumption trends may shift toward other regions, particularly those experiencing population growth, in South America, Africa, and Asia. According to the State Department, one of the most significant and troubling developments in international drug trafficking trends is the spread of synthetic drug consumption. In the Middle East and in some parts of Asia, for example, synthetic drugs have become the primary drug threat. Drug overdoses associated with heroin and other opioid use continues to remain the primary contributor to drug-related deaths. The global illegal drug trade represents a multi-dimensional challenge that has implications for U.S. national interests as well as the international community. In 2012, some 95,000 to 226,000 deaths worldwide were reported to have occurred as a result of drug use. Drug use and addiction have been said to negatively affect the social fabric of communities, hinder economic development, and place an additional burden on national public health infrastructures. Intravenous drug users are at particular risk of contracting diseases such as Hepatitis B, Hepatitis C, and HIV/AIDS. Observers suggest that drug trafficking also represents a systemic threat to international security. Revenue from the illegal drug trade provides international drug traffickers with the resources to evade government detection; undermine and co-opt legitimate social, political, and economic systems through corruption, extortion, or more violent forms of influence; penetrate legitimate economic structures through money laundering; and, in some instances, challenge the authority of national governments. In the process, some warn that transnational networks of criminal safe havens exist in which drug traffickers operate with impunity. As highlighted by the use of West Africa as a major cocaine transit hub for Latin American drug traffickers, criminal actors prey on states with low capacity for effective governance or the enforcement of the rule of law. This can exacerbate preexisting political instability, post-conflict environments, and economic vulnerability. By many accounts, drug trafficking, state weakness, political corruption, and powerful criminal organizations are part of a seemingly self-perpetuating cycle. On the one hand, a drug trafficking presence in a country can increase corruption and undermine political stability, while on the other hand, social and political instability may be causal factors for attracting a thriving drug industry. Further, academic literature on conflict duration indicates that control of a lucrative illegal drug trade in the hands of a particular political actor, rebel, or insurgent group can lengthen a conflict. State powers in the hands of a DTO or TCO through deeply entrenched kleptocracy serve as a force multiplier to enhance a criminal organization's power by harnessing the capacity of a state's infrastructure—roads, seaports, airports, warehouses, security apparatus, justice sector, and international political sovereignty—to further the group's illicit business aims. The consequences of a thriving illicit drug trade co-located in a conflict zone are illustrated today in Afghanistan, where some portion of drug-related proceeds annually help facilitate the current insurgency. In other regions, such as in the Western Hemisphere, Americans have been murdered, attacked, taken hostage, and tortured for their involvement in counternarcotics operations—highlighting the past and ongoing dangers associated with the international drug trade. In addition, some observers are concerned about the potential spread of DTO- and TCO-related violence from Mexico into the United States. Moreover, several groups listed by the U.S. Department of State as foreign terrorist organizations (FTOs) are known to be involved in drug trafficking. James R. Clapper, the Director of National Intelligence, presented the intelligence community's annual threat assessment to Congress in early 2015 and highlighted, among other issues, drug trafficking as a major transnational organized crime threat to the United States.