The Korean war was a very costly military conflict for the United States. There were more than 36,000 deaths and more than 100,000 wounded soldiers for the U.S. alone. The was war dragged for more than 3 years and shortly after it began it converted into a stalemate with the South Korea being supported by the United States and and North Korea by the Chinese, who did not want and in-flood of refuges coming to its land.
As a consequence of this stalemate, The United States strengthen ties with South Korea and provided military, economic and technological help to them and still continue to do so.
We are still suffering from the consequences of this war which has not officially ended.