North Korea gets their citizens in fear by showing them propaganda about the United States.
Most likely federal, as monarchy isn't a strong central government, it's a one person government with optional advisors. A federal government implies a democratic style of leadership with a main government instead of separate small ones within a country.
The 2010 Census enumerated 308.7 million people in the United States, a 9.7 percent increase from 281.4 million in Census 2000. Of the total population in 2010, 300.8 million lived in 116.7 million households for an average of 2.58 people per household.
