Recent attacks abroad — in London, Manchester and Tehran— as well as attacks at home, make us think of the ways in which we're all vulnerable.
Today, we suffer under the constant threat of terrorism. At this point, we're used to heightened security at the airport or at tourist destinations. But what about the threats that come on ships, over our waterways and through our ports?
The US and North America have two large oceans. And obviously, that's a significant layer of defense from anyone who wants to get here, but it's not an impossible barrier.