Why did the United States launch the US-Mexico War and occupy half of Mexico? The reason why the United States did this is actually for one thing, opening up the road to the Pacific Ocean and expanding to the Pacific coast. Only two countries occupy the Pacific coast. One is England and the other is Mexico. Britain-controlled Canada is a part of it. The United States dare not do this, because the United States suffered losses in Canada and almost died.

There is also Oregon, which is disputed by the United States and Britain. But at first, neither the United States nor Britain dared to act rashly. And Mexican territory. Although Mexico was comparable to the United States in territory at that time, it was far from the United States in strength. So the United States went to war with Mexico. We won't talk about the process, it's all an excuse. Let's see why we didn't continue to occupy Mexico after the war.

First of all, the purpose of the American war has been achieved. The United States acquired land to the Pacific Ocean. And a large area of land. There is no need to continue attacking Mexico. And Americans understand one thing: after land is acquired, it must be digested, otherwise it is very likely to be taken away by other countries. This was very normal at that time. So the next step for the United States is to slowly digest these lands, so there is the famous westward movement. The United States began to fully develop the western region.

Secondly, although the United States won Mexico, it paid a very high price. In this war, the United States participated in 59,000 wars and killed more than 1.3 million people. When Mexico entered the war, there were at most 60,000 people,16,000 people died. The casualties on both sides are equal. The United States also spent $97.5 million. This was a huge sum of money at that time. In other words, the price paid by the United States is very high. If we continue to fight, the United States may be dragged down by war.

There is also a very prominent domestic contradiction in the United States. Since the founding of the United States, the southern States and the northern States have been arguing over whether to keep slaves. Later, the dispute was put on hold temporarily, but with the expansion of American territory, this contradiction became more and more prominent. Because the choice of system after the new country joins is very important, both sides hope that the new country will adopt its own system. So the contradiction became more and more fierce. Finally, the famous civil war broke out. At this time, the United States simply has no time to invade other countries.

Finally, it is very difficult for the United States to destroy Mexico. At that time, the United States was able to beat Mexico. Because most of the land in northern Mexico belongs to the United States, there are fewer Mexicans. Mexico has very weak control over these places. Unlike the south, it has a strong control. This is also a reason why Mexico failed. If the United States wants to continue to fight south, it will be difficult to succeed.

In any case, the border between the United States and Mexico has been determined since then. But now, life in the territory annexed by the United States far exceeds that of the Mexican people. This can be said to be very important.