The purchase of Alaska in 1867 marked the end of Russian efforts to expand trade and settlements to the Pacific coast of North America, and became an important step in the United States rise as a great power in the Asia-Pacific region.
There has been a debate about border control. Donald Trump wants to take action through buidling a wall along the border but the democrats do not want this. This creates a policy gridlock, where no policy is passed due to each party not wanting the other party to get its way.
I think 5 but might want to make sure