North Korea’s state-run media reported the country is “carefully examining” plans to attack the U.S. territory of Guam on Wednesday. The plans include using medium- to long-range ballistic missiles.

The threat is unsurprising for the more than 160,000 people who live on the small island, roughly the size of Chicago, in the western Pacific Ocean.

Guam is the largest and most southern island in the Mariana island chain. Part of Micronesia, Guam lies about 3,800 miles west of Honolulu, Hawaii. Dededo is the most populous village on the island.

The indigenous people are referred to as Chamorros and are considered U.S. citizens by birth. However, residents of the colony do not pay U.S. income taxes or vote for president.

In addition to having their own popularly elected governor and a small legislature, Guam sends a non-voting delegate to the U.S. House of Representatives. In the 1980s, the residents of Guam wanted to become a commonwealth on par with Puerto Rico, but their efforts failed.

The island was claimed by the Spanish in 1565 and became a U.S. territory in 1898, after the Spanish-American war. Japanese forces briefly occupied the island from 1941 to 1944, but the United States recovered it in 1944. In 1950, the island became an unincorporated territory of the United States.

Guam is home to several bases for U.S. armed forces, including the Navy, Air Force and Coast Guard. A defense system is already in place, — the U.S. Army’s Terminal High Altitude Area Defense, or THAAD — which protects the island by shooting down ballistic missiles. It is the closest U.S. territory to North Korea.