Major General William C. Chase, U.S. Army, observes "Operation Portrex" D-Day maneuvers on Vieques, Puerto Rico, 8 March 1950.<br>
The objective of "operation Portrex" (for Puerto Rico Exercise) was to see how the combined forces of the U.S. Army, Marines, Navy, and Air Force would do as "liberators" of an enemy captured territory (Vieques) against the "aggressors".
U.S. Army Signal Corps photo <a rel="nofollow" class="external text" href="https://www.history.navy.mil/content/history/nhhc/our-collections/photography/us-people/m/matthews-francis-p/sc-338221.html">SC 338221</a>