The strikes that have been sweeping Poland in recent days constitute more than just the most serious wave of labor unrest there since 1980.

So far, the government's response - with some arrests and a lockout - seems mild compared to the harsh repression that greeted the previous wave of strikes in the early part of this decade.In any event, the new strikes represent the most significant threat to the communist regime since Gen. Wojciech Jaruzelski imposed martial law and outlawed the Solidarity labor organization, the first independent labor federation in the Soviet bloc.

Likewise, the strikes pose what could be a major embarrassment to Russian leader Mikhail Gorbachev.

Even an indirect Soviet crackdown to maintain Kremlin control over Poland would, as John Hughes notes in his column on this page, shatter the genial image that Gorbachev has been trying to project to the non-communist world.

Such a crackdown would be particularly embarrassing just when the Soviets are to start pulling out of Afghanistan and when Gorbachev is about to sit down with President Reagan at another major summit meeting.

At the heart of the latest strikes are worker demands for sizeable wage hikes to help offset the sizeable price hikes recently imposed by the government. But when Solidarity founder Lech Walesa demanded Wednesday that the government legalize the banned union, the strikes became highly politicized, too.

Whatever the immediate outcome of the latest strike may be, it should be clear by now to both Gdansk and Moscow that the restless Poles will keep pressing for as much reform as can be permitted by a government that can't afford to antagonize neighboring Russia too much.

The strikes are more than a test of how much Gdansk and Moscow will tolerate. They also are a test of how much new communist leaders have learned about political and economic realities.

One of those realities is the simple fact that no nation can overcome economic stagnation like that besetting Poland as long as either military leaders or politicians insist on monopolizing decision-making powers and suppressing the creative powers of the people.

At this point, negotiations seem unlikely. If Gen. Jaruzelski should agree to discussions with Walesa, such a breakthrough just might indicate the communist leaders have learned an important lesson. But if the talks never take place, the latest strikes seem likely to be just another frustrating chapter in the long and unhappy history of repression in Poland.