To be successful, or to be in a thriving condition.
For Italy, they were spies who collected top secret knowledge for the Allied Powers. They were U.S. soldiers who fought off the enemy successfully. They were British troops leaving their units to join the enemy.
The US government supported Cuba in the Spanish-American War because A the government viewed Cuba as a nation in need of independence. Granted, the United States wanted Cuban independence from Spain so that the US could exert indirect political and economic control over the nation, its peoples, and its resources.