On the first day of August 1985, just before dawn, several hundred contras hurled themselves into a surprise attack on the town of La Trinidad, straddling the strategic northern highway to Managua. They were deep inside Nicaragua, nearly halfway to the capital. The size and speed of the assault shocked the Nicaraguan Army and impressed foreign observers. The Nicaraguan rebels, it seemed, were a more dangerous force than they had been given credit for.
La Trinidad, however, turned out to be the peak for the contras, and a costly one at that. The Popular Sandinista Army, after chasing the guerrillas back into the surrounding hills, estimated that only half of the rebels escaped unhurt. Never since has the Nicaraguan Democratic Force (FDN) staged such an ambitious raid.
But now, with $70 million in United States military aid flowing to the contras, and President Reagan planning to ask for another $105 million in the coming fiscal year, the rebels are under pressure to show more daring again.
``The contras have got to produce something down there before June,'' when Congress is expected to debate the next contra aid bill, a congressional aide says. ``They need a big hit to give them big momentum, and under those circumstances, the vote won't go against them.''
Skepticism about the contras' military muscle has deepened among US lawmakers and Western military observers here over the past 12 months. The first 11 months of 1986, when the rebels' official US aid was limited to $27 million in humanitarian assistance, saw no serious contra attempt to take the initiative. Rather, the contras' largest military force, estimated to have 10,000 to 12,000 men, found itself bottled up in its Honduran base camps, hemmed in by Nicaraguan ground troops and artillery.
``We've given them aid and for what?'' complains a Senate aide critical of US support for the contras. ``There is nothing there. They have no control over territory, nothing. They are just camped in Honduras.''
Contra leaders, however, say they have no intention of trying another La Trinidad-style attack in the near future to prove their military viability.
``We will simply follow traditional guerrilla tactics, choosing targets at our convenience, without falling into the trap of aiming for spectacular objectives,'' says Ernesto Pal'acios, Washington spokesman for the contras' political organization, the United Nicaraguan Opposition (UNO).
``The military field is the Sandinistas' strongest one,'' he argues, and it would be foolhardy for the rebels to overreach themselves.
``At the moment,'' adds FDN leader Adolfo Calero, ``we are limiting ourselves to expanding our presence inside Nicaragua. Taking territory and holding it will come later.''
About 3,500 newly trained and supplied guerrillas have slipped into Nicaragua over the past month, since the dry season began, FDN leaders say. The Sandinista authorities put the figure far lower, at 1,500, but acknowledge that the rebels have been getting in.
The Sandinista Army, says spokeswoman Rosa Passos, ``has been in constant combat'' against the infiltrators, trying to keep them on the run.
``From our perspective, 1,500 is not a large number,'' she adds. ``This is simple infiltration that they have needed to do for a long time. So long as they have money and camps in Honduras, it is natural that the contras will infiltrate, and it's a constant battle: They come in, and the Army fights them.''
After failed attempts last November to enter Nicaragua in large numbers from the so-called Las Vegas Salient, where their main camp is located, the FDN units appear to have moved east up the Honduran border before crossing it, Western observers say.
``They had to quit slamming their heads against the Sandinista artillery in the salient and go east,'' says a military analyst familiar with the border situation.
The contras who have entered Nicaragua in recent weeks have so far had little impact. Instead, they appear to be avoiding contact with Sandinista troops, and heading south for a three- or four-week march to link up with an FDN unit based inside Nicaragua: the Jorge Salazar regional command. That unit, estimated at between 1,000 and 2,000 strong, has been operating in central Nicaragua for nearly two years, though its actions have been limited to ambushes on Army and civilian vehicles, and hit-and-run attacks on farming cooperatives, Nicaraguan government officials claim.
The Jorge Salazar unit has the only real base inside Nicaragua on which the FDN can now build, after the FDN's extended withdrawal from serious operations, military analysts here say.
Although some 8,000 rebels were active in Nicaragua in 1984, Sandinista Army officials say, Nicaraguan Army offensives in both the north and south in 1985 drove almost all of them into neighboring Honduras and Costa Rica.
This success prompted Managua to claim it had inflicted a ``strategic defeat'' on the contras, from which no amount of US aid could rescue them. The recent contra infiltrations have not changed the Sandinistas' views.
``The overall process is one of tremendous defeat'' for the rebels, Captain Passos says. ``The number of men they have inside does not mean they have broken the balance of power.''
Indeed, the balance of military power seems unquestionably in Managua's favor: The rebels' southern front is in disarray and numbers no more than a few hundred men. Most of the Miskito Indian guerrillas on the Atlantic coast are observing a cease-fire or negotiating with the Sandinistas. And the Sandinista Army has fielded 60,000 men above and beyond reservists and militia forces.
Some rebel leaders, acknowledging this situation, put their faith in a popular insurrection against the government and point to the Sandinistas' own victory in 1979 over the far superior forces of then-President Anastasio Somoza Debayle.
Adolfo Calero, for example, is confident that if his men can wage ``generalized guerrilla warfare that is impossible to hide,'' Nicaraguans discontented with their government will ``become aware of the vulnerability of the Sandinista regime.
``Political discontent and our nonconventional war will merge'' into a popular uprising, Mr. Calero says.
Few diplomats in Managua share that belief. Even those who detect widespread dissatisfaction with the Sandinistas see the opposition as poorly organized, divided, and closely monitored by government security services.
The poor prospects for an insurrection have led some contra advisers, notably Arturo Cruz Jr., son of UNO leader Arturo Cruz, to consider what they call a ``long march'' approach. Mr. Cruz Jr., laid out his thinking in a recent issue of Commentary magazine. In the article, he writes off the chances of either an insurrection or a US invasion and argues that the contra army should be prepared to wage a long-term struggle to ``buy the time it needs to strengthen its political base in Nicaragua and beyond.''
But this strategy gets short shrift from Calero. ``You plan a prolonged popular war when those running the war have to indoctrinate the people, sell them an ideology,'' he argues. ``That doesn't fit our case because we don't have to do any convincing - the people are with us.''
``We have to fight this war in the shortest time possible,'' Calero insists.
A long, drawn-out war would also seem unsustainable in the US, Washington political analysts argue.
``A prolonged war would be totally destabilizing to the region, and there is just not enough money here to do it,'' one Senate aide says.
The question remains as to whether the FDN's military chiefs - even if politically convinced of the need for a prolonged war - are militarily capable of carrying it out.
One of the contras' main weaknesses, both Sandinista Army officers and Western military observers here say, is their lack of tactical know-how in organizing small unit operations.
Sixty-seven contra field commanders have now completed a six-week course run by US Army Special Force Groups (Green Berets), Calero announced last week. That course, understood to have been given in the US, included lessons on guerrilla tactics, infiltration, mission planning, rapid reaction, psychological operations, and intelligence gathering, among other skills, according to UNO military secretary Luis Rivas.
Some 600 contra unit commanders are due to take similar courses over the next year, Calero said.
The US Congress, which voted the funds for such training, will be looking for results on the battlefield before it votes on further contra aid.
That, as contra leaders themselves acknowledge, is not a realistic prospect for the coming months. But less ambitious goals, suggested by Cruz Jr., have yet to appear like real possibilities.
In his Commentary article, Cruz suggests as measures of contra success ``whether the resistance can challenge the internal security network, can destroy communications facilities and significant military installations, can coordinate a variety of military operations at once, and can rally defectors from the Sandinista Army.''
For a guerrilla army that has scarcely even attempted such operations, and that has been effectively out of the field for 18 months, that is a very tall order.