CASTRO'S Cuba, clinging to its lonely hard-line Communist ideology, is battening down for rough times. A few days ago, Cuba's Soviet mentors agreed not on the usual, five-year economic aid and trade agreement, but instead on a one-year agreement the details of which have not been revealed.
It probably will hit Cuba hard. Gone are the favorable aid deals that used to be cut with Cuba and countries like Vietnam and North Korea.
Now Cuba will have to pay in convertible currency at world prices for what it buys from the Soviets. That probably means a reduction in the supply of Soviet oil to Cuba - oil that used to be shipped in at very favorable subsidized rates.
Already Castro has ordered his people to replace oil and electric power with manual labor and animal power.
Several hundred thousand bicycles have been ordered from China to replace automobiles.
Oxen are to replace tractors in the fields.
Horses are to pull carts through the streets of Havana in place of trucks.
Says one knowledgeable observer: ``Castro is taking Cuba back into the last century.''
Some experts predict that as a result of all this, Cuba's GNP will decline by 25 to 30 per cent this year. This coupled with food shortages and other inconveniences will mean tougher times for Cuba's ordinary citizens. Water is sometimes short in Havana, where a population of a million has outstripped the government's ability to provide water and efficient sewerage.
While Cuba can probably survive cutbacks in its Soviet oil imports, hitherto about 30,000 barrels a day, much more serious would be disruption of Soviet wheat exports to Cuba. The ability of the Soviet Union to provide wheat from areas like the Ukraine and Byelorussia, given political unrest in those areas, may be in question.
The Soviets are cutting back their assistance to Cuba for two reasons. One is their own economic problems at home, which preclude being as helpful to allies as they once were. The other is President Gorbachev's disaffection with Fidel Castro's unyielding hard line. Unmoved by the changes elsewhere in the communist world, Castro preaches Marxist orthodoxy at home and confrontation with the Americans abroad. Moreover, US intelligence agents are convinced that he still continues supplying weaponry to Marxists in Nicaragua and to the communist rebels in El Salvador.
However, Castro may be something of a beneficiary from the complexity of Soviet politics in Moscow. Says one expert on Cuba: ``The Russians may be tightening up on Castro, but Gorbachev's not about to pull the rug out from under him. All the time at home, Gorbachev's looking over his shoulder at the military. Gorbachev's not going to get into trouble with the military by losing that electronic eavesdropping base the Soviets have at Lourdes (near Havana).''
The base, which permits the Soviets to monitor phone calls and satellite transmissions in the United States, would cost millions of dollars to replace.
Intelligence experts say that while a Cuban submarine facility used by the Soviets is useful, it is the Lourdes electronic monitoring station that is of paramount importance to the Soviet military.
What does all this portend for the change in political systems in Cuba that many believe is inevitable? Some experts believe it will be very different in character from the way change came to the Communist nations of Eastern Europe.
``In Europe, Gorbachev abdicated,'' says one. ``The Soviet army was ordered not to fire on people who started demonstrating for freedom. The repressive apparatus was neutralized. That's when the people took over. But in Cuba there is no hint that repression is being curtailed. Quite the reverse. The regime is becoming harsher and more cruel. So you will not see progressive demonstrations against the regime. There will simply be an explosion, and it will be more violent than that which took place in Romania.''
If this prediction is correct, when will the explosion occur? Says this expert: ``1991 will be the critical year.''