Brazil has not been invaded since 1865 during the Paraguayan War. Additionally, Brazil has no contested territorial disputes with any of its neighbors and neither does it have rivalries, like Chile and Bolivia have with each other. The Brazilian military has also three times intervened militarily to overthrow the Brazilian government. It has built a tradition of participating in UN peacekeeping missions such as in Haiti, East Timor and Central African Republic. Brazil signed the UN treaty on the Prohibition of Nuclear Weapons.