David Ignatius

U.S. adversaries exploit power gaps. It's easier for Russia to invade Ukraine with irregular forces out of uniform, the so-called 'little green men,' than to send a conventional army that would challenge NATO.

In 1967, the world health community launched a global effort to eradicate smallpox. It took a coordinated, worldwide effort, required the commitment of every government, and cost $130 million dollars. By 1977, smallpox had disappeared.