Italy’s populist government has relished defying the European Union, and its latest showdown with Brussels could threaten the continent’s fragile recovery—and the global economy.

Since the shah’s ouster in February 1979, Iran’s Islamic regime has been propelled by Ayatollah Khomeini’s revolutionary vision and underpinned by its animus toward the United States.

Algerians are protesting in large numbers over moves to maintain ailing longtime leader Abdelaziz Bouteflika in power. The ruling elite faces a test of legitimacy that could spark unrest in a region …