Manifest Destiny is the 19th century belief that it was America’s fate to expand. As said by John L. O’Sullivan in the U.S. Magazine, “The time has come for everyone to stop hampering our power, limiting our greatness, and checking the fulfilment of our manifest destiny…” What Sullivan is trying to say is that it is our fate to develop and expand our country, so there is no reason for people to continue to try to interfere with our ability to do so. Everyone including Mexico knows that it is our destiny to expand, so why do they even try to stop us? The United States will continue to expand west, until it reaches the Pacific Ocean. Also according to John L. O’Sullivan, “Mexico never can exert any real government authority over such a country.” Mexico was the same size as the United States, but it was not as powerful. Sullivan is saying that this is the reason why Mexico will probably continue to lose land to the U.S. He says that California will also soon fall for this reason. Of course we had the right to go to war if Mexico tried to deny our fate of expanding.
On the other hand, some people believe that the United States was not justified in going to war with Mexico, because the President intended to go to war with Mexico. They think that he intended to put the U.S. though war, and purposefully sent troops into the disputed territory. This is not true