Reasons why this may not be such a big deal: 1. Diesel-electric submarines from various countries (including, I think, Germany and Australia) have been known t

Reasons why this may not be such a big deal: 1. Diesel-electric submarines from various countries (including, I think, Germany and Australia) have been known to lurk near US aircraft carriers before. It's not that surprising that a Chinese one managed it too. 2. We don't know whether the submarine actually managed to sneak up on the carrier, or whether it just lurked at the bottom and waited for it to approach. 3. The Kittyhawk is an old carrier and doesn't have all the anti-submarine warfare capabilities of the newer ones. 4. For all we know, the carrier might have detected the submarine anyway and decided to pretend it didn't, so they can avoid giving away how good their sonar actually is. Regardless of what the British tabloids might think, I don't necessarily think this represents a "serious geopolitical change".