After spending many years in Mexico and heavily involved in radical political activities, Siqueiros went to Los Angeles in 1932 to continue his career as a muralist. Working in a collective unit that experimented with new painting techniques using modern devices such as airbrushes, sprayguns and projectors, Siqueiros and his team of collaborators painted two major murals. The first, "Street Meeting", was commissioned for the Chouinard School of Art. It depicts a group of workers of mixed ethnicities listening to an angry labor agitator's speech during a break in the workday. The mural was washed over within a year of its unveiling—due both to weather-related technical issues, and perhaps, to the pro-Communist content of the work. Siqueiros' other significant public Los Angeles mural, ' (full name: ', or "Tropical America: Oppressed and Destroyed by Imperialism"), was commissioned shortly after the unveiling of "Street Meeting", and was to be painted on the exterior wall of the Plaza Art Center that faced the busy Olvera Street. "Tropical America" depicts the United States' imperialism in Latin America, a much more radical theme than was intended for the work. Although it received generally favorable criticism, some viewed it as "Communist propaganda", which led to a partial covering in 1934 and a total whitewash in 1938. Eighty years later, the Getty Conservation Institute performed restoration work on the mural. As no color photographs of "Tropical America" are known to exist, conservators used scientific analysis and best practices to get at the artist's vision of his piece. It became accessible to the public on its 80th anniversary, October 9, 2012. The América Tropical Interpretive Center that opened nearby is dedicated to the life and legacy of David Alfaro Siqueiros.