Walling The World

"What do Tijuana, Baghdad and Jerusalem have in common?

They all have walls that divide neighbors, cause controversy and form part of an array of physical barriers around the world that dwarf the late, unlamented Iron Curtain.

There are walls, fences, trenches and berms. Some are reinforced by motion detectors, heat-sensing cameras, X-ray systems, night-vision equipment, helicopters, drones and blimps. Some are still under construction, some in the planning stage.

When completed, the barriers will run thousands of miles, in places as far apart as Mexico and India, Afghanistan and Spain, Morocco and Thailand, Malaysia and Saudi Arabia, and Iraq.

They are meant to keep job-hungry immigrants, terrorists and smugglers out, thwart invaders, and keep antagonists apart....While security and immigration control are the most frequently cited reasons for building border walls, politics play a key role in some countries. In others, fortifications serve to translate territorial claims into concrete facts on the ground."