ica. Those who have come into contact with Mexican civilization along the border, too, have been, to a large extent, that portion of the American people who have had closest contact with the negro population of the republic and regard them, and to hardly a less degree any colored or mixed blood people, as unquestionably inferior. To the Mexican this attitude is a constant irritation.
Contrast in language and civilization accentuates frontier problems. On our northern boundary there is neither. Immigrants pass in both directions hardly conscious that the boundary exists. The flowing into Canada of an agricultural population from the United States occurred without clash. A similar movement could not take place from the United States to Mexico. To be sure, there is a border belt in which there is a population to some degree bi-lingual and large numbers of Mexicans, especially since the revolution, have sought an opportunity for a more secure livelihood across the border. But the average Mexican in the United States remains a foreigner in habits of life. For him, on account of a combination of elements including race, lack of education, and lack of resources, it is hard to become a part of the life of the new community in which he finds himself. In many cases he does not wish to do so.
Americans of the border states of Mexico also seldom identify themselves with the local life. They keep their American citizenship; they may be engaged in the exploitation of mines, lumber, or other natural resources, but they are representative of a "foreign interest." Even though they become landowners, they continue to
