Mexico's cartels are still at it. A 400-yard drug tunnel portal has been discovered, linking San Diego and Tijuana. It’s enough to make a Brooklyn Bridge sandhog envious, complete with air ventilation chambers, power and room enough to stretch your legs as you stroll under the border. Strangely, the image of Captain America—the Marvel superhero and one-time champion of American youth propaganda—was printed on the plastic wrapping of many bricks of the 17 tons of marijuana seized. Whose side is he on? A recent surge in subterranean activity has showcased the cartels' relentless industriousness: more than 70 tunnels have been discovered in the last two years. The cartels have employed some imaginative and sometimes bizarre methods to move their profitable products. Earlier this month, two giant, drug-slinging catapults were seized by the Mexican Army near the border, and underwater submersibles have also been discovered, their hulls full of contraband.