The federal government guarantees the states a republican form of government, protection, and territorial integrity. give examples of how each of these guarantees are carried out.

Guarantees the states a republican form of government - congress allows senators and representatives from a state to take their seats in congress. This is in recognition of the States' republican form of government.

Guarantees protection - any attack on a state is deemed an attack against the United States of America. Thus, each state is under the protection of US Armed Forces, Navy Seals, etc.

Guarantees territorial integrity - the national government can't create a new state in the territory of an existing states. Borders are recognized to differentiate one state from another.