Can someone answer this please why is a government presence important when traveling or living somewhere? or is it important?

So that there can be some authorities present to keep people in check.

The president of the united states does not have the authority to “limit” the power of the judicial branch. however, the president can influence the political direction of decisions made by justices on the supreme court through the nomination process when a position becomes available.i would say the best answer is that he can at least interpret the laws