What challenges do experts think the united states will face in the future?

Well i'll give you 10 you can choose which 4 u like best:

1.)Marriage Rights

2.)The Decline of Privacy

4.)A Massive Regulatory Burden( Affordable Care Act)

5.)Ending the Drug Crisis/War

 8.)The Age of Preemptive War

(d) rivers.

explanation:

civilizations developed around rivers because their waters provided places to hunt and fish. also, as the rivers flooded, the lands around them became fertile. this allowed them to support farming. this is especially true of the nile river, which flooded the same time each year.

four sitting presidents have been assassinated while in office but the first was abraham lincoln,