Dangerous Waters is a book that shows the 21st century pirate problem is increasing, not abating.
Piracy are getting worse, especially around the Muslim countries - although there is a problem in this hemisphere as well. Some parts of the global oceans and waterways are essentially lawless. Even the largest ships, such as super tankers, are habitually in danger and frequently boarded and robbed by bands of pirates. Sometimes the ships are actually hijacked, the crew murdered or put in slavery, and the ships turned into false-flagged "ghost" ships, run by criminal syndicates for stolen or dangerous cargo. They can also be used as part of an Al Qaeda Navy.
Heaven help you if you are on a private boat trying to navigate some of these waters!