Federalism meaning power is shared between the national and state governments. Separation of powers into branches that make, enforce or interpret laws. Balance of Power - controls (checks) can be made on the other branches. Limited government - everyone is bound by the US Constitution.
Yes you are right, voting is the best important civic responsibility. Civic responsibility or civic engagement refers to the sense of personal responsibility citizens feel to uphold their duties or obligations as part of the community.
The thirteen American colonies declared their independence from Britain in seventeen seventy-six. But they had to win their independence in a long war that followed. During that war, the colonies were united by an agreement called the Articles of Confederation.