"When I was in London, talking with Lord Beaconsfield, he spoke of Mexico. He said he wished to heaven we had taken the country, that England would not like anything better than to see the United States annex it. I suppose that will be the future of the country. Now that slavery is out of the way there could be no better future for Mexico than absorption in the United States. But it would have to come, as San Domingo tried to come, by the free will of the people. I would not fire a gun to annex territory. I consider it too great a privilege to belong to the United States for us to go around gunning for new territories. Then the question of annexation means the question of suffrage, and that becomes more and more serious every day with us. That is one of the grave problems of our future."
January 1, 1970
https://en.wikiquote.org/wiki/Mexico