Political alliance is an agreement between political parties to work together and share resources and votes in order to achieve a greater chance of success in elections. This happens all over the world and can even involve parties of opposing ideologies, but is often necessary for democracy to function. The term can also be applied to international coalitions aimed at fighting terrorism and other global threats.
Since the Age of Exploration, alliances have played a central role in international politics and the balance of power between states. Attempts by a single country to establish hegemony over other countries usually fail because the rivals of that state form an alliance against it. For example, King Louis XIV’s attempts to dominate continental Europe led to the War of the Grand Alliance, and Napoleon’s plans for empire were thwarted by a series of alliances against him.
At the international level, alliances are more formal and often take the form of treaty agreements committing allies to join in military or other co-operative efforts against a common enemy. The anti-communist alliances of the Cold War were one such arrangement, as are the multilateral collective security arrangements like NATO and the ANZUS Pact.
Increasingly, alliances at the domestic political level are taking the form of electoral blocs, with parties sharing voters and contesting elections as a united front. A notable example is the Juntos por el Cambio big tent coalition in Argentina which includes Republican Proposal, the Radical Civic Union and the Civic Coalition. In Australia, the centre-right Coalition of the Nationalist Party and Australian Country Party has been an electoral alliance since 1927.