Eritrea's attack on Djibouti sent that message, an echo of the message Iran sends every time it threatens to close the Strait of Hormuz. That strait connects the Indian Ocean and Persian Gulf, and at least 30 percent of the world's oil supply transits Hormuz in tankers. Close the Hormuz chokepoint, and you damage modern economies. Threaten to close it, and the price of oil spikes -- and Iran's mullahs pocket the cash. (As a historical note, today's United Arab Emirates, next door to Hormuz, was once a "pirate coast," with Hormuz providing targets.)

This isn't a conspiracy theory, it's geo-strategic choke point reality. Local and even tribal issues actually propel many small-scale conflicts around the globe, but geography attracts other interested parties and troublemakers. Radical Islamists were very interested in the Achehnese rebellion on the Indonesian island of Sumatra. Yes, they shared religious concerns, but Aceh Province also bordered the entrance to the Straits of Malacca, which connect the Indian and Pacific Oceans.

The U.S. Navy will argue that completely closing a major strait like Hormuz is tough to do, and the Navy is correct. But if an admiral says he hasn't pondered the military, economic and political challenges presented by near-simultaneous (likely coordinated) outlaw attacks that affect two or three major straits, he's spinning you.

Cyber attackers also probe for digital chokepoints. Computers guide America's electrical grids -- they are an information nexus. Two weeks ago, U.S. intelligence agencies revealed that hackers (likely from China and Russia) had inserted software that "could damage (electrical grid) infrastructure." Blackouts wreak economic havoc. Knocking out power nationally is a psychological and political shock. Cyberspace is complex terrain, but the same idea obtains: squeeze a vulnerable throat.