In this media age, complex events throughout the world tend to get boiled down into simple catch phrases. For instance, the five-year-old war in Afghanistan is now frequently summed up in news reports as "Russia's Vietnam." In this case, the instant analogy has the ring of truth.
It is certainly true that in Afghanistan the Soviet Union has committed itself to an unwinnable and apparently interminable war. In the Vietnam days, they called such a situation a quagmire.
During the five years they have occupied Afghanistan, the Soviets have had to commit a larger and larger chunk of their resources just to hold their ground. At first the Soviet forces were supposed to supply reinforcement and air support for the Afghan army; but as the war has dragged on, Soviet troops have taken over more and more of the ground-based combat duties.
As in Vietnam, the local army has proved unreliable, unwilling to fight against its own people, and prone to desertion. In another Vietnam echo, it has been reported that Soviet troops, stationed far from home among a hostile population, suffer low morale and have fallen into widespread drunkenness and drug abuse. Afghanistan, like Indochina, boasts a plentiful, potent, and inexpensive supply of marijuana and opium to distract the occupiers.
The similarities between Afghanistan and Vietnam run much deeper than these matters of appearance; they are political and moral as well. Like the Vietnam war, the Soviet presence in Afghanistan represents a superpower's heavy-handed attempt to impose an unpopular and essentially alien regime on a Third World peasant society.
The Soviets of course have their ideological and public relations justifications for their Afghan adventure. They are defending "socialism." They say they entered Afghanistan at the invitation of its government to defend the Afghan "revolution" against outside interference from the CIA.