A member of the Siberian Battalion of the Ukraine's Armed Forces International Legion smokes a disposable vape during military exercises, amid Russia's attack on Ukraine, at an undisclosed location in Kyiv region, Ukraine on December 13, 2023. (Photo by Valentyn Ogirenko/Reuters)

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 U.S. Army crew chief flying on board a CH-47F Chinook helicopter observes the successful test of flares during a training flight in Afghanistan, March 14, 2018. (Photo by Tech. Sgt. Gregory Brook/Reuters/U.S. Air Force)

A serviceman of the Carpathian Sich Battalion is seen at his position on a frontline, as Russia's attack on Ukraine continues, near the town of Lyman, Donetsk region, Ukraine on December 8, 2022. (Photo by Viacheslav Ratynskyi/Reuters)

A Ukrainian serviceman walks an empty street in the front line city of Bakhmut, in Donetsk region, Ukraine on February 25, 2023. (Photo by Serhii Nuzhnenko/Radio Free Europe/Radio Liberty)

Young recruits of the 72nd Chorni Zaporozhtsi Separate Mechanized Brigade of the Ukrainian Armed Forces attend an exercise, amid Russia's attack on Ukraine, in Kyiv region, Ukraine on April 5, 2025. Ukraine's Defence Ministry launched a recruitment drive for young people, 18- to 24-year-olds, to serve in the military for a year for the equivalent of about $24,000 and hefty bonuses. (Photo by Gleb Garanich/Reuters)

Ukrainian territorial defence soldiers from the Donetsk Oblast fire D-20 artillery in the direction of Toretsk, Ukraine, 24 July 2025. (Photo by Diego Herrera Carcedo/Anadolu via Getty Images)

A Ka'apor Indian warrior (L) chases a logger who tried to escape after they captured him during a jungle expedition to search for and expel loggers from the Alto Turiacu Indian territory, near the Centro do Guilherme municipality in the northeast of Maranhao state in the Amazon basin, August 7, 2014. Tired of what they say is a lack of sufficient government assistance in keeping loggers off their land, the Ka'apor Indians, who along with four other tribes are the legal inhabitants and caretakers of the territory, have sent their warriors out to expel all loggers they find and set up monitoring camps in the areas that are being illegally exploited. (Photo by Lunae Parracho/Reuters)