The one in which all Americans can agree ?
Usually, the American society is divided in the discussion of key topics. not only based on the alignment of individuals to one of the set political parties but based on public opinion and political culture on its own. if you interviewed 50 Americans on topics such as immigration, gun control, abortion, healthcare, amongst others; odds are you would have a very evenly split number of opinions for and against these topics. However, one topic in which a greater portion of Americans would agree on is the importance of national security, that being by the protection and improvement of the work of security agencies such as the FBI or the CIA or the better implementation of visible security forces such as the local police or the TSA in airports.
Public opinion on national security is a pretty important aspect of American culture, since the country has been subject to major threats and attacks in the past, and understandably people want to be able to live and raise a family in an environment where they feel safe and confident that their government is doing all it can to ensure their safety and that of their families. I would argue that in this instance government is working effectively in ensuring this demand that has so much public support. This is evidenced by the 17 national agencies that make up the US intelligence community. Most of these agencies might not even be known to many Americans however, they are constantly working on the national security issues, and work tirelessly to ensure that Americans can live safely in their country.
http://www.latimes.com/nation/la-na-17-intelligence-agencies-20170112-story.html