As the Soviet Congress opened 10 days of meetings on Monday, the USSR is at a crossroads of leadership and policymaking that is unprecedented.

In the past congresses, the deputies representing every major territorial district in the nation have assailed Mikhail Gorbachev for dictatorial and sly methods - but then approved every reform he sought, often denouncing him as they voted yes.The most recent major change, last spring, amended the constitution to end the Communist Party's guaranteed monopoly on power.

This time there was an emotional call from one of the deputies for Gorbachev's removal from office because of "devastation, hunger, cold, blood and tears." But her motion for a vote of no-confidence was resoundingly defeated.

Thus far it appears that Gorbachev is more unpopular than he has ever been in his own country - but that he retains firm political control. He called for a referendum on the future of the Soviet Union and warned that perestroika is threatened unless action is taken.

He wants a restructuring of the union and a streamlined presidency - without a return to dictatorship. The next few days will tell whether he will succeed, but he is unlikely to face an organized challenge from either radical reformers or hard-liners in the congress.

Nevertheless, the acceptance of foreign aid to cope with the food crisis is a national embarrassment to many, and the country's political divisions are abundantly evident.

In spite of the grave economic crisis, an alternative to Gorbachev at this point could threaten all of the positive changes of the past year. His political and economic struggles this week will be watched closely by a world anxious for continued Soviet reform.