To interpret the laws....thats what the judicial branch does. But, what are the choices?
In return for the money, the United States got Texas, California, New Mexico, and large areas of Arizona and Nevada. This was great for them because it worked well with the manifest destiny idea and it enabled them to get to the western coast.
At first, Abraham Lincoln refused to react to the secession of the southern states. As president of the Union, he viewed the Confederates as states in rebellion--but they were not a separate nation in his eyes, not yet.
Answer: Abraham Lincoln