What kind of government system is characterized as a group of states United by a central authority but retaining local or regional power

When france sneezes, europe catches cold.what did prince metternich mean by this statement? people in france are more likely to get sick than people elsewhere. europeans elsewhere are often inspired by events in france. happenings in france rarely spread across borders. all damaging incidents in europe start in france.

How do the public-safety regulations protect workers ? regulations create advertising laws

To your knowledge had the usa ever invaded canada after the war of 1812