The role of the Vice President in the U.S. government primarily involves acting as the President's key advisor and stand-in, particularly in the event of the President's absence, illness, or incapacity. The Vice President also plays a vital role in the legislative process by casting tie-breaking votes in the Senate and being a member of the National Security Council. Additionally, the Vice President often represents the administration in diplomatic missions and engages with various constituents, enhancing the political agenda of the administration they serve.