Eugenia León's song by the middle of the documentary is incredibly moving as it touches the most sensitive buttons in the national sentiments of Mexicans. If I caught the lyrics correctly, it links the current situation to the U.S. invasion in the 1840s (by which the U.S. chopped off and swallowed one half of Mexico), the French invasion of Mexico in 1864, the imposition of Maximilian of Habsburg as emperor of Mexico, and the relentless resistance by president Benito Juárez, the first Indigenous president in Latin America.
http://video.google.com/videoplay?docid=-8136401529506488350