A pedestrian passes by a television screen displaying a map of Japan (R) and the Korean Peninsula, in Tokyo on August 29, 2017, following a North Korean missile test that passed over Japan. Japan's Prime Minister Shinzo Abe on August 29 said North Korea's launch of a missile over its territory was an "unprecedented, serious and grave threat" as he called for an emergency UN Security Council meeting. / AFP PHOTO / Kazuhiro NOGI (Photo credit should read KAZUHIRO NOGI/AFP/Getty Images)
Residents cover their heads while taking shelter during an evacuation drill for North Korean missiles in Wajima, Ishikawa prefecture on August 30, 2017, one day after a North Korean missile test that passed over Japan. Nuclear-armed North Korea said on August 30 that it had fired a missile over Japan the previous day, the first time it has ever acknowledged doing so. / AFP PHOTO / JIJI PRESS / STR / Japan OUT (Photo credit should read STR/AFP/Getty Images)
A woman walks in front of a huge screen displaying Japanese Prime Minister Shinzo Abe (L) and US President Donald Trump (R) in Tokyo on August 29, 2017, following a North Korean missile test that passed over Japan. Abe said on August 29 that he and US President Donald Trump agreed to hike pressure on North Korea after it launched a ballistic missile over Japan, in Pyongyang's most serious provocation in years. / AFP PHOTO / Kazuhiro NOGI (Photo credit should read KAZUHIRO NOGI/AFP/Getty Images)
Trucks from the Japan Air Self-Defense Force carrying PAC-3 surface-to-air missile launch systems arrive at US Yokota Air Base for a temporary deployment drill in Tokyo on August 29, 2017. Some 50 Japanese servicemen took part in the drill. / AFP PHOTO / Toru YAMANAKA (Photo credit should read TORU YAMANAKA/AFP/Getty Images)
Soldiers from the Japan Air Self-Defense Force set up PAC-3 surface-to-air missile launch systems during a temporary deployment drill at US Yokota Air Base in Tokyo on August 29, 2017. Some 50 Japanese servicemen took part in the drill. / AFP PHOTO / Toru YAMANAKA (Photo credit should read TORU YAMANAKA/AFP/Getty Images)
