The presence of the blacks is the greatest evil that threatens the United States. They increase, in the Gulf States, faster than do the whites. They cannot be kept for ever in slavery, since the tendencies of the modern world run strongly the other way. They cannot be absorbed into the white population, for the whites will not intermarry with them, not even in the North where they have been free for two generations. Once freed, they would be more dangerous than now, because they would not long submit to be debarred from political rights. A terrible struggle would ensue.