Citizen participation is essential to the preservation of the U.S. political system because it helps the U.S. political system make laws and give out a vote from the people to the president.
No you must be a citizen.
Yes, definitely. You do not need to be a US citizen to bring a lawsuit in the US court system.
Yes, you can enlist in the US military without being a citizen. There are restrictions in the type of MOS you can participate in. And the service can accelerate the citizenship process.
Congress
democratic
democratic
by encouraging them to view members of competing parties as enemies
A citizen that wants to be President of the US has to be at least 35 years old, in order to participate in the presidential campaigns, and become President of the US. (NOTE: Only US born citizens can become president of the US, this includes Alaska & Hawaii)
Voters. People who can vote are able to cast their ballot for the candidates of their choice. In the US, any citizen over the age of 18 can register to vote, and participate in local and national elections.
Voting is critical to maintaining a representative system.
Immigration judges grant political asylum, the US Citizen and Immigration Services division of Homeland Security monitors.