Guam, a U.S. territory in the western Pacific Ocean, is tiny - but its strategic location is of great importance, especially to the U.S. military.

(REUTERS/Erik De Castro )

(REUTERS/Erik De Castro)

(REUTERS/Erik De Castro )

(REUTERS/Erik De Castro )

(REUTERS/Erik De Castro )

(Richard P. Ebensberger/ REUTERS)

(U.S. Navy/REUTERS)

(Jeff Landis/REUTERS.)

(FILE/REUTERS)

(AP Photo/Tassanee Vejpongsa)

(AP Photo/Tassanee Vejpongsa)