In the spring of 1940, Nazi Germany under Hitler invaded Norway, Denmark, the Netherlands, Belgium, and France. Meanwhile, in September of that year, Imperial Japan invaded and conquered French Indochina while simultaneously fighting China during the Second Sino-Japanese War. There had been growing concern in Alaska over the lack of military defense, as it was vulnerable to Axis invasion. Gruening had been pushing for defense facilities in Alaska since his appointment to the governorship, and because of recent actions from Germany and Japan, Congress designated funds to build army forts and airfields in the territory. By 1941, there were 3,000 U.S. Armed Forces soldiers stationed around Alaska. With the attack on Pearl Harbor, Gruening prepared for Alaska to be next. Plans were made for black-outs and civilian defense forces whose first assignment was "around-the-clock protection for radio stations, telephone exchanges, oil tanks, public utilities, and docks, and to be vigilant against possible sabotage." The armed forces expanded their operations in Alaska, slowly moving toward the Aleutian Chain, the most accessible route from Asia. The Japanese did reach Alaska in June 1942, bombing Dutch Harbor and landing on the islands of Attu and Kiska, the only continental U.S. locations captured during World War II.