A Saudi women’s rights activist was driving in the United Arab Emirates when she was pulled over by security officers, thrown on a plane to Saudi Arabia and jailed.

In Canada, when a Saudi student refused to stop making YouTube videos criticizing the kingdom’s rulers, two of his brothers back home were imprisoned.

So when a prominent Saudi critic, Jamal Khashoggi, disappeared after entering the Saudi Consulate in Istanbul last week, it hardly surprised Saudi dissidents living abroad — until Turkish officials said they believed he had been killed.

Even for a country that has long used fear and enticements to control dissent, the prospect that the state had killed a well-known dissident writer in a foreign country represented a startling escalation.