Think about how multifaceted US policy is on any given day of the year. The economist boils down similar issues to a blurb on a page with a heading that says "middle east." So now you can turn that page and be confident that for this week you know what's going on in the middle east.
The truth is the economist fills a void. Before reading an issue you know nothing about current events in India. After reading you know something. Something is vastly more power than confessing ignorance in any situation. And if anyone questions you, well, the economist said so.
I think I'm justified in being skeptical.
I think they're assuming their readers will know how to dig further on events they find relevant. Personally I find The Economist pairs well with a subscription to Foreign Affairs.
Reading a single issue will not make you well-informed; at most it will provide you with something to chat about at a cocktail party (if you're the sort of person who likes to chat about the news) or a point of reference if you meet someone from a foreign country and want to ask a topical question.
I've found that reading over time is advantageous, not because one collects more and more trivia about more and more places (although that's true) but because the more important themes emerge of their own accord most of the time. By this is I mean that one tends to become aware of major issues long before they rise to the top of the 24 hour news cycle.
Mounting a challenge within an institutional or constitutional framework is qualitatively different - it puts the rule of law above pure power politics.