Google’s high-handed tactics with US regulators have come back to haunt it, with critics saying the tech giant set the stage for a dramatic showdown with the Department of Justice nearly a decade ago. The DOJ last week sued Google, accusing it of using anti-competitive tactics to maintain its search engine’s dominance over rivals. The focus of the suit — massive cash payments to smartphone makers like Apple and Samsung to make Google’s search engine the default option on their devices — is a fresh one. But industry sources say the Silicon Valley giant has nevertheless made itself vulnerable to...