The John C. Stennis Carrier Strike Group, which includes five US naval vessels, made a high-profile appearance in the South China Sea a few days ago, angering many in China. When I asked Mark Toner, State Department deputy spokesman, on Monday whether such a move was raising tensions in the Asia-Pacific region, he repeated his government's talk of the US exercising freedom of navigation rights. The US will continue to do so in accordance with international law, he added.

Common sense tells us that everything which is not forbidden is allowed. Let's assume for a moment the five-day show of the John C. Stennis Carrier Strike Group in the South China Sea was in accordance with international law. Still, it does not mean it did not escalate tensions there.

Also, it is absolutely legal for a passerby to stand and look into your house. But it will make you feel uneasy, even angry, if he/she keeps doing it every day. And he/she will drive you crazy by standing on the sidewalk outside your house for hours with a Swiss army knife in hand.