Fifty men from Kahnawake volunteered to fight with the United States armed forces during the Vietnam War. While working to strengthen their culture and language, the people of Kahnawake have generally not had the political turmoil of the nearby, smaller Kanesatake reserve. In support of Kanesatake during its Oka Crisis in 1990, people from Kahnawake blocked the Honoré Mercier Bridge to Montreal, which had an access road through their reserve. The Kanesatake reserve had been blockaded and isolated by the Sûreté du Québec in a conflict over use of lands the Mohawk considered sacred. The bridge blockade affected the commute of many locals throughout the summer, leading to rioting and the burning of effigies, and to the "Whiskey Trench" episode. On August 28, 1990 a convoy of 50 to 75 cars, bearing mostly women, children and elders, left Kahnawake in fear of a possible advance by the Canadian Army. While the Mohawks' cars were being searched by the provincial police force, a crowd of hundreds gathered on the Montreal side of the highway; many in the crowd threw rocks and chairs at the cars and yelled ethnic slurs. Many windows were broken and some Mohawk were hit by rocks and cut by glass. Thirteen people were arrested. Blame has fallen on the provincial government for letting the convoy pass; on the Sûreté du Québec for holding the cars for so long, and for mostly not stopping people from throwing rocks; on the lack of police or army or riot squad; and on local radio stations that broadcast the location of the convoy. After some time, Kahnawake negotiated separately with the armed forces to remove the blockade to the bridge. In 2007, two vessels operated by the Sea Shepherd Conservation Society flew the Kahnawake Mohawk flag. The Kahnawake Mohawk nation is the only indigenous American sovereign nation to have deep-sea foreign-going vessels flying its flag. Since December 2007, the Sea Shepherd vessels have been registered in the Netherlands. Kahnawake contains three National Historic Sites of Canada: Fort St-Louis, the Jesuit Mission of St. Francis Xavier, and the Caughnawaga Presbytery. Kahnawake has several media outlets:  The pow wow is held every summer on the second weekend of July at the Kateri Tekakwitha Island.It is a social event open to everyone to share the Native American culture such as traditional foods, hand made crafts, singing and traditional dancing.