Tactics reminiscent of the early American frontier days are now being used in Vietnam. Lieutenant Commander Donald D. Sheppard, UBN, of Coronado, California, aims a flaming arrow at a bamboo hut concealing a fortified Viet Cong bunker on the banks of the Bassac River, Vietnam on December 8, 1967. (Photo by AP Photo)

A woman wearing a face mask walk through Shinjuku area on January 07, 2021 in Tokyo, Japan. Japanese Prime Minister Yoshihide Suga is set to declare a state of emergency in Tokyo and neighboring three prefectures, Kanagawa, Saitama, and Chiba on Thursday, following the recent surge in COVID-19 cases in the region. Tokyo saw over 2000 new cases per day for the first time on January 7, 2021. (Photo by Yuichi Yamazaki/Getty Images)

This photograph taken during a government organised media tour shows people in traditional costume standing in Potala Palace Square as the Potala Palace – classified as a World Heritage Site by Unesco in 1994 – is seen in the background in the regional capital Lhasa, in China's Tibet Autonomous Region, on June 1, 2021. (Photo by Hector Retamal/AFP Photo)

Supporters celebrate as they watch official results from the Union Election Commission on an LED screen in front of the National League for Democracy Party (NLD) head office in Yangon, November 9, 2015. Myanmar's ruling party conceded defeat in the country's general election on Monday, as the opposition led by democracy figurehead Aung San Suu Kyi appeared on course for a landslide victory that would ensure it can form the next government. "We lost," Union Solidarity and Development Party (USDP) acting chairman Htay Oo told Reuters in an interview a day after the Southeast Asian country's first free nationwide election in a quarter of a century. (Photo by Soe Zeya Tun/Reuters)

Rebel fighters from the Jaish al- Fatah (or Army of Conquest) brigades manoeuver an alleged explosive- rigged make- shift armoured vehicle during a major assault on Syrian government forces West of Aleppo city on October 28, 2016 Syrian opposition fighters launched a major assault on government forces to break a months- long siege of rebel- held neighbourhoods of the battered city of Aleppo. Rebel groups including the powerful Ahrar al- Sham faction and former Al- Qaeda affiliate Fateh al- Sham Front fired waves of rockets into government- held western Aleppo, killing at least 15 civilians, a monitor said. (Photo by Omar Haj Kadour/AFP Photo)

Employees of a food stand take pictures of Titan, a robot created by England Cyberstein Robots, performing at the Danilovsly market in downtown of Moscow, Russia, 12 May 2014. Titan visited to Moscow to attend “Bal Robotov”, an interactive exhibition of the most recent advances in robotics which will be opened on 15 May in Artplay Moscow exhibition center. Titan worked alongside superstars including Will.i.am, Rihanna, Will Smith and Jackie Chan. (Photo by Sergei Ilnitsky/EPA)

People wear face masks as they ride an E-scooter in the Old Elbe Tunnel in Hamburg, Germany, Thursday, October 15, 2020. To avoid the spread of the coronavirus the use of a face mask in the 117-year-old tunnel under the Elbe river is mandatory. (Photo by Michael Probst/AP Photo)

(L-R) Ruby Zinner, 21, Caroline Reinstadler, 22, Marie Kallis, 22, and Julia Bogdanoff, 21, wearing graduation caps and gowns drink champagne while taking graduation photos in Washington Square Park amid the Coronavirus pandemic on May 09, 2021 in New York City. Due to the ongoing coronavirus pandemic NYU's commencement ceremony will be held virtually on May 19th. Students from the 2021 will be invited back for an in person graduation when public health guidelines allow. (Photo by Alexi Rosenfeld/Getty Images)