Why Alan Pope's near-miss on HMS Oryx mattered

Why was the CIA pilot Alan Pope's missed attack on HMS Oryx so consequential?

The miss let the incident be set aside; hitting and sinking the British submarine would have created a serious alliance crisis.

The follow-up grounds the earlier hypothetical about an intelligence agency attacking an ally in a specific near-miss. The failed attack could be put to one side precisely because Alan Pope did not hit the Royal Navy submarine. The claimed identification of a supply-smuggling submarine is implausible, and many mistakes led to the attack. A hit, especially one that sank Oryx, would have forced those errors into the open and created a much larger Anglo-American crisis.