TOKYO — Soon after troops invaded Ukraine in February 2022, Western leaders expelled hundreds of Russian spies from their capitals and blacklisted companies with ties to the Kremlin.The coordinated effort was intended to make it harder for the Kremlin to collect intelligence and buy equipment like microchips, transmitters, and the machinery used to make weapons.Since then, officials say, dozens of those banished spies have turned up in an unexpected place: Japan.The country’s weak espionage laws and flourishing high-tech industry have made it a crucial piece of the Russian war effort. About 90 percent of Russian missiles and drones contain Japanese...