MOSCOW — Let the Middle East and North Africa be buffeted by populist discontent over repressive governments. Here in Lenin’s former territory, across the expanse of the old Soviet Union, rulers with iron fists still have the upper hand.

Their endurance serves as a sobering counterpoint for anyone presuming that the overthrow of a tyrannical regime by a broad-based movement is inevitably followed by vibrant democracy.

The long-serving president of the former Soviet republic of Belarus, for example, won another term in December with 80 percent of the vote, then took great offense when the results were called shamefully implausible by his opponents. (They have not been heard from since.)

Over in Kazakhstan, the even longer-serving president has had himself coroneted with the formal title of “national leader.”