News around the world in recent months tends to give the impression that Soviet leader Mikhail Gorbachev has become one of the "good guys," with glasnost in his own country, a missile treaty with the U.S., and a warm, friendly summit in Moscow with President Reagan.

But those outward appearances should not blind the world to a basic fact - the Soviet Union is still opposed to the democratic principles upon which Western nations are based. And the Kremlin will still lie, cheat, and steal from the West whenever it can.This week's spy case in Canada ought to be a reminder of those differences and the need to be on guard.

Apparently uncovered by the defection of a Soviet aviation official in Montreal, the spy ring involved at least 17 Russian diplomats and other officials. Eight have been expelled from Canada and nine others who had already left the country were barred from ever returning.

In their usual response to being caught red-handed in espionage, Moscow kicked out five Canadian officials and blamed the whole thing on some irrational Canadian desire to spoil relationships with the Soviet Union just when East-West ties were improving.

It's true, the timing is bad. But what were the Canadians supposed to do - close their eyes to the spy ring as a gesture of East-West friendship? It was the Soviets who were engaged in industrial espionage and in trying to penetrate Canadian military intelligence.

As an FBI agent pointed out in a recent letter to the Deseret News, at least a third of all Soviet diplomatic personnel sent abroad are agents of the KGB, the Soviet secret police, or the GRU, Soviet military intelligence.

Those expelled from Canada included diplomats, journalists, trade delegates, aviation specialists, and an airline official.

It was in Canada in early 1946 that the first big spy case after World War II was broken. The defection of a Russian embassy attache uncovered the theft of atomic secrets, shocked the Western allies, and helped propel the world into the growing Cold War.

The excuses given by the Soviets this week sound very much like the statements made in 1946 - claiming innocence and blaming Canada for catching the Russian spies. The latest spy case and the Soviet reaction to it, indicate that not much has changed in the past 42 years.

That's a point to keep in mind as Gorbachev smiles, says all the right things, and makes unsuspecting friends around the world.