The American presence began to grow throughout Mexico and it grew even stronger after the U. This was happening because the Union Generals such as Grant and Sherman were leading the establishments of may of the major Railroads because of their victory of the South. The south's defeat was a key reason why they did not have a strong influential presence on the New American Frontier like the North Did. America's presence was strongly influenced when President Lincoln chose Tom Scott as a Secretary of War and Procurement. Scott's influence was very strong because he was a well connected man. He was the President of the Penns RR which was the #1 industrial corporation of the world which gave him many financial allies. Scott's job was to organize all of the necessary contacts (bringing all the financial elites together). Moses Taylor was a big financial elite. He was the Pres. Of Citibank, and he also managed the Aster Empire. John Jacob Aster specialized in Frontier capitalism. The citibank was the primary force for the American Frontier. American Presence became even stronger because of all the different technologies needed. It took a lot of hard work and a lot of know how in order to build thing such as RR's. Griswall invented the Bessemer Patent (which hardened rails) which caused conflict with the financial allies because he was a southerner. I mention this in particular because this is one critical patent that came from the south. One the contrary, most patents came from the north and in Britain because they were more high tech than the south and had more financial capital (most Financial elites empires backed North) as well. Without financial capital and the know-how, it would have been hard to build such things as RR's. Many critical components went into the building of RR's. The engines themselves required a lot of skill. Manufacturers needed steel as well as boilers; a critical part and took a lot of skill to build.