Which word best explains nationalism? loyalty ambition confidence gratitude

The best word is "loyalty"

Nationalism is a sense of identity related to the nation you live in, and a related sense of duty and loyalty to that country. Nationalism involves a feeling of connection to your nation, and can include an unquestioning fealty to its leaders. This can be a dangerous thing, as many leaders use nationalism to consolidate power and to justify aggression toward other countries. 

LOYALTY best explains nationalism.

With the system of separation of powers, each branch has a specific function. No branch can do it all under this system. The legislative branch has the responsibility of making laws. At the federal level, this is our Congress that consists of the House of Representatives and the Senate.

Explanation: They should have this power because they were taught and brought up to know thee best options and what to do for the government.