Former colonel Enrique Bermudez entered the little arms warehouse and smiled at two photographs nailed to the wall above a pair of crossed rifles.

"The president and the defense minister," he laughed, pointing out the images to visitors at his sprawling headquarters camp in the rugged hills that make up the Honduran-Nicaraguan border.

On the left was Adolfo Calero, chief political figure of the Nicaraguan Democratic Force, the largest and most powerful by far of several organizations fighting to overthrow the Sandinista government in Managua. On the right was Bermudez himself, who helped found the group while Calero was still in Nicaragua. Since the Sandinista takeover in 1979, he has been struggling to rid the country of its new rulers.

The comment was made in jest. Coming from the man who more than any other has brought guerrilla war and sabotage to the Sandinistas, however, it provided a clear reminder of the dual personality that inhabits the Nicaraguan Democratic Force and the rebel movement.

The group, known as FDN by its Spanish-language initials, has expanded from a band of ex-National Guard officers into a mainly peasant army, backed by a political organization headed by Calero and other civilian opponents of the late dictator Anastasio Somoza.

President Reagan, appealing for funds to finance the rebels' war, described the political leaders last week as former participants in the Sandinista-led revolution of 1979 who now seek to recover frustrated democratic ideals with U.S. help.

On another level, however, the one where command decisions are taken and war is actually fought, the FDN has remained a military organization largely commanded and inspired by a determined former National Guard officer who declares he will want a share of power in Nicaragua if the Sandinista government is ever overthrown.

"The only way one can influence is from inside," Bermudez told a questioner about his political future in the event of victory. "Yes, I would like to be where I could have some kind of influence, so all we have told our fighters about our principles would not be deviated from or distorted."

The debate in Washington over renewed U.S. funding for the rebels has centered on the FDN. The organization received the bulk of $80 million in CIA financing from 1981 until last spring and likely would receive most of any further funding.

Other groups, more involved with the Sandinista revolution and less hostile to its original principles, have operated from Costa Rica, but with smaller amounts of U.S. money that never permitted them to build the kind of military threat headed by Bermudez.

Bermudez, 52, was Somoza's military attache in Washington when the dictator fell from power. Bermudez said he immediately began organizing the fight against the new revolutionary leadership.

Through three incarnations of the FDN's political leadership from 1980 until now, he has remained the major military figure. Bermudez received the rebels' first help from Argentine intelligence officers, he said, and worked directly with the CIA when U.S. money and advice replaced the Argentines in 1982.

After two shakeups, Bermudez has organized a lean staff along military lines and an army divided into eight regional commands and half a dozen other units. Of his forces, estimated at 14,000, mostly peasants, he said 40 officers and about 200 fighters served in Somoza's National Guard, including himself and the most prominent of his regional commanders.

Despite his pivotal role in the rebel war, Bermudez said he has never traveled to Washington to lobby congressmen on behalf of the administration request for another $14 million to aid the movement. "This is because I eat babies," he joked, referring to denunciations of his National Guard past.

Calero, a businessman who left Nicaragua at the end of 1982, has been the group's chief representative in Washington and elsewhere, raising funds from a dubious Congress and, since last spring, from private and semipublic backers here and abroad. Since October 1983 he has headed the FDN National Directorate and carried the title of overall commander.

The relationship between Calero and Bermudez has defined authority within the rebel organization, with contributions from a handful of civilian and military aides in Honduras or Miami, explained Edgar Chamorro, who was expelled as a directorate member last November.

The directorate was chosen by the CIA in late 1982 to enhance the FDN's political appeal in Congress and public opinion, according to Chamorro and other Nicaraguan exiles involved at the time. Bermudez was the only previously active rebel leader to figure in the new leadership. According to other rebels, his ties to U.S. intelligence and military officers had locked him firmly into the movement.

Bermudez has freely acknowledged his career in the National Guard. But he has insisted -- and even committed critics of the FDN agree -- that he never played a role in atrocities or abuses carried out by National Guard troops during the civil war leading to Sandinista rule.

"I believe I served my country in an institution that was constitutional at that time," he said. "I'm satisfied with myself, with what I did."

In fact, Bermudez was absent throughout the war. As military attache in Washington, he said, "I watched the war on television." Also as military attache, he consolidated the U.S. contacts that, he added, proved helpful in building the FDN and gaining U.S. funding.

Partly as a result, U.S. backing for the rebel effort in 1982 through May 1984 flowed chiefly from the CIA to Bermudez's military organization. Chamorro said that during his time on the directorate he and his colleagues were rarely informed on these military matters, leaving the political leadership with a mainly representative role.

In one reflection of this, Indalecio Rodriguez has been the only civilian directorate member resident in Honduras, the insurgents' headquarters. Rodriguez, a former university dean who was active against Somoza, has taken special interest in Nicaraguan refugees and combatants' families.

Other members of the directorate since 1982 have been Alfonso Callejas, Marco Zeledon and Lucia Cardenal, who spend most of their time in the United States. Until his split, Chamorro also had resided mostly in Honduras. He was thrown out of the organization after he made a series of public complaints against the way it was run by Bermudez and Calero.

Calero, 53, has been the most active and visible civilian leader as head of the directorate. He also has taken command of a civil-military junta designated to make operational decisions.

Calero, who managed the Coca-Cola bottling plant in Managua, was a key figure also with Zeledon in organizing strikes against Somoza during an uprising against the dictator. Neither he nor other members of the directorate served in the Sandinista government after Somoza fell, however, and only Rodriguez was active in armed rebellion against the dictator's rule.

Callejas was a minister and vice president under Somoza but resigned in 1972 in disagreement with the government. Cardenal is the widow of Jorge Salazar, a prominent businessman who shielded clandestine Sandinistas under Somoza but turned against them when the leftist direction of their government became clear after 1979.

Rebel leaders most closely tied to the original Sandinista revolution have remained outside the FDN. These include Eden Pastora, a hero of that war, and Alfonso Robelo, a businessman who served in the first Sandinista government until he became disillusioned and went into opposition in exile.

Together with Miskito Indians, labor leaders and other groups, they formed the Revolutionary Democratic Alliance based in Costa Rica in 1983. Because of Pastora's prickly independence and a reluctance to be seen as a vehicle of U.S. policy, their guerrilla war never received the level of support offered to the FDN in Honduras.