On February 22, 1969, during Operation Dewey Canyon in Quang Tri Province, he was wounded twice. He was wounded the first time in the shoulder when his company was attacked by a large enemy force. A first lieutenant at the time, Fox then personally neutralized one enemy emplacement and directed his company to destroy others. After his company's executive officer was mortally wounded, he continued to direct the company's actions, ordering air strikes and coordinating the advance until the enemy retreated; Fox, the only officer left in his company that was capable of resisting the enemy, was wounded again in the final assault, but refused medical attention while he reorganized his troops and prepared the wounded for evacuation.