Coups succeed when enough people believe they will succeed
Between 1950 and 2010 researchers counted 457 attempts to seize power by coup, and almost exactly half worked. What decides the outcome, once troops are moving, is less firepower than perception: plotters win when they convince officers and officials that victory is already inevitable, so resistance looks pointless.
A coup d'état, French for a stroke or blow of state, is usually an illegal, open attempt by the military or other elites to remove those in power. When a leader who took office lawfully then clings on unlawfully, it is called a self-coup. An early English appearance came in 1785, in a translated letter from a French merchant complaining about a royal decree restricting British wool imports, and the British press later applied the term to the violent methods of Napoleon's secret police.
Clayton Thyne and Jonathan Powell's dataset shows 227 successes and 230 failures in those sixty years. Africa and the Americas saw the most attempts, about 36.5% and 31.9% of the total, while Europe had just 2.6%. Activity peaked in the mid-1960s, with further surges in the mid-1970s and early 1990s. Successful coups have become rarer, and those after the Cold War have been likelier to produce democracy, though most still entrench authoritarian rule. A country's past coups strongly predict future ones, a pattern known as the coup trap.
Rulers try to protect themselves through coup-proofing: stacking the army with relatives or members of trusted ethnic and religious groups, and splitting security forces into rival agencies. The trade-off is weaker armed forces, because loyalty beats competence in promotions. Failed attempts in authoritarian states tend to make the ruler stronger.
The vocabulary is rich. A palace coup swaps one ruling faction for another; most Russian tsars between 1725 and 1801 either lost or gained the throne that way. Putsch, Swiss German for a knock, was coined for a Zurich uprising in 1839 and later attached to Hitler's failed Beer Hall Putsch of 1923. From Spanish come the pronunciamiento, a formal declaration deposing a government, and the cuartelazo, a barracks revolt. Plotters sometimes call their coup a revolution to borrow democratic legitimacy.
Source: Coup d'état
