However, this ongoing technological progress became questionable when the atomic bomb threatened to wipe humanity off the face of the earth.

threatened 是动词 threaten 的过去式，threaten 的意思是"威胁、恐吓"，指用言语或行动表示要造成伤害或不利。 在这个句子中，threatened 表示原子弹对人类的潜在危险，暗示可能带来毁灭性后果。