although the role of the executive varies from country to country, usually it will propose the majority of legislation, and propose government agenda. in presidential systems, the executive often has the power to veto legislation. most executives in both systems are responsible for foreign relations, the military and police, and the bureaucracy. ministers or other officials head a country's public offices, such as a foreign ministry or defence ministry. the election of a different executive is therefore capable of revolutionising an entire country's approach to government.