For many people, foreign affairs have a real fascination. John Locke explains some of that fascination in section 14 of his 2d Treatise on Government: On Civil Government:
It is often asked as a mighty objection, where are, or ever were there any men in such a state of nature? To which it may suffice as an answer at present, that since all princes and rulers of independent governments all through the world, are in a state of nature, it is plain the world never was, nor ever will be, without numbers of men in that state. I have named all governors of independent communities, whether they are, or are not, in league with others: for it is not every compact that puts an end to the state of nature between men, but only this one of agreeing together mutually to enter into one community, and make one body politic; other promises, and compacts, men may make one with another, and yet still be in the state of nature. The promises and bargains for truck, &c. between the two men in the desert island, mentioned by Garcilasso de la Vega, in his history of Peru; or between a Swiss and an Indian, in the woods of America, are binding to them, though they are perfectly in a state of nature, in reference to one another: for truth and keeping of faith belongs to men, as men, and not as members of society.
Because foreign affairs are still in the state of nature, we can see the state of nature in the daily news. Moreover, in foreign affairs, we see the contours of the basic ethical obligations that human beings owe to one another. When almost all other nations agree that nation A has acted badly, it reveals part of the law of nature on which John Locke bases so much of his analysis. More generally, paying attention to when a nation comes under general criticism in foreign affairs will teach you much about the law of nature.
As a somewhat lame example, think of the interpretive principle that foreign affairs are in the state of nature in relation to the duty of helping those in distress that is part of the law of nature. If Nation B, which had done no great wrong to its neighbors suffered a catastrophic earthquake, and its neighboring nations who were in a position to do so quickly were reluctant to help, appropriate opprobrium would fall upon those neighboring nations. Just so, if you as an individual are the one on the spot available to help someone who is drowning, it is incumbent upon you to help to the limit of your abilities.
Section 14 of the 2d Treatise would be remarkable for the insight that we see the state of nature before us in the daily news alone. But what I love most of all in this section is its evocation of promise-keeping as part of the law of nature: "... truth and keeping of faith belongs to men, as men, and not as members of society." The making and keeping of promises is a key part of what makes us human. If we are, indeed, made in the image of God (contrary to my teleotheistic credo that it is our job to build God) this making and keeping of promises, compacts, treaties and covenants is surely one of the most important ways in which we are made in God's image.