| If it's an accident? An apology, maybe. If it damages something or someone? If relations between the two countries are not completely wretched, usually a bunch of arguing, and small reparations [1][2]. If they are completely wretched, or there's some other concern at play, usually nothing [3]. The victim country is free to apply whatever sanctions it sees fit. These sorts of questions are not settled in a framework of legality, as much as they are settled in a framework of power, and willingness to escalate. Escalating against a nuclear sovereign is often a bad idea. [1] https://en.wikipedia.org/wiki/Kosmos_954 > For the recovery efforts, the Canadian government billed the Soviet Union Can$6,041,174.70 for expenses and additional compensation for future unpredicted expenses; the USSR eventually paid Can$3 million. [2] https://en.wikipedia.org/wiki/Iran_Air_Flight_655 > As part of the settlement, even though the U.S. government did not admit legal liability or formally apologize to Iran, it agreed to pay US$61.8 million on an ex gratia basis in compensation to the families of the Iranian victims [3] https://en.wikipedia.org/wiki/Korean_Air_Lines_Flight_007 > The Soviet government expressed regret over the loss of life, but offered no apology and did not respond to demands for compensation. |