CAIRO (Reuters) - The Muslim Brotherhood is facing an old adversary in the fight of its life, but has few means to confront the Egyptian military that has swept it from power. Reduced to camping out on the Cairo streets, all it can do, it seems, is mourn its dead.
The deaths of 51 Brotherhood supporters killed when the army opened fire on them on Monday was the latest and bloodiest blow to a group reeling from President Mohamed Mursi's dramatic ouster from office at the hands of the generals.
Even as the bloodshed may help it rally supporters around a sense of shared suffering, the Brotherhood faces big questions: how will it manage the internal divisions likely to result from its failure; should it re-engage in electoral politics; and what happens to leaders whose policies got it into this situation.
How the Brotherhood responds will determine much of the fate of the biggest Arab nation, whose economy is on life support and whose allies abroad are anxious it does not descend into chaos.
Near the Rabaa Adawiya mosque in northeast Cairo, where men who last week ran ministries now shelter from the baking sun - and in some cases from the police - Brotherhood spokesman Gehad El-Haddad was asked what came next after the killings: "More anger," he said. "More anger in people's hearts. More sorrow."
The Brotherhood called for more big rallies on Tuesday. That keeps up pressure on the army to offer the security looked for by the investors, and tourists, Egypt's finances badly need.
Among men providing the Brotherhood camp's own security, Mohamed Wahab, 32, said he was ready for an army attack: "We expect it and we are waiting," he said. "If they want to come, we are here. If they want to kill us, we are ready to die."
Some of his fellow sentinels carried batons, though Wahab himself carried only an iPad: "But we will never stop being peaceful," he said. "Even if they shoot us, even if we die."
Many outsiders doubt the Brotherhood's leadership would ever reverse outright a non-violent strategy dating back decades.
But the army's move against the electorally victorious Mursi also raises the risk, voiced by Brotherhood leaders, that some Islamists will now conclude that the path to power runs through bombs and bullets, not the ballot box.
Discipline has long been a defining characteristic of the 85-year-old movement. "Stand firm" say badges worn by the baton-wielding volunteers manning the makeshift fortifications around the sit-in. A sign rendered in broken brick sends a message to the army helicopters above: "Martyrdom or Legitimacy".
It seems directed as much at its own followers as at the generals it accuses of a coup against the legitimate head of state. Its command chain shaken by arrests and morale sapped by the worst setback in its history, the Brotherhood hopes to rally its people around a call for passive resistance until death.
It was deeply divided before, however, over whether to seek executive office - many argued that winning the presidency was a trap set by those who wanted the Brotherhood to fail. Mursi's downfall seems likely to reopen debate on long-term strategy.
"The Brotherhood don't have a clear mind to think about the future. What they are doing now is a last attempt to maintain solidarity," said Khalil al-Anani, a Brotherhood expert. "The unity of the Brotherhood is at stake."
For that reason, talking of the "martyrdom" of those who died on Monday offered the movement an opportunity to rally its base, Anani said: "This is a very good chance for them to increase public support and to mobilize their rank and file."
But fighting back militarily was not an option: "They know very well that they cannot challenge the Egyptian army," he said. "They are just trying to put more pressure on the army."
Addressing the crowd at Rabaa Adawiya on Friday, Brotherhood leader Mohamed Badie reminded them that military courts had long sent its members to the gallows and had sentenced them to a collective 15,000 years in jail: "You have lived together and sacrificed together," he said, to roars of approval.
"Our bare chests are stronger than bullets," he added - a refrain commonly heard in the sit-in extending several hundred meters (yards) out into the streets leading to the mosque.
"MARTYR IN WAITING"
Loyalists from the Brotherhood's Nile Delta heartlands have come to man the barricades. Others have journeyed from farther afield: Ahmed Sadaat, 30, said he had flown back from Dubai.
"Martyr in the making" said a slogan printed on paper and pinned to his chest as he manned a checkpoint at one entrance to the sit-in, wearing Ray-Ban sunglasses and a motorcycle crash helmet, with an Egyptian flag tied around his neck.
"What happened here is not democracy," he said. Nearby, Mohamed Attallah, a 52-year-old mathematics teacher from Tanta in the Nile Delta, hands out bottled water. "We felt freedom," he said. "We don't want the freedom we felt to disappear."
The army, which says one officer died and 40 were injured at the barracks where protesters were shot on Monday, has so far left this protest, just over a mile away, alone. It is keeping its distance, seemingly hoping it may exhaust itself.
The military says it removed Mursi in response to huge protests against his rule. Millions took to the streets on June 30, the anniversary of his first year in office, to demand he leave power. They cited grievances including economic stagnation and perceptions of a power grab by a president who was either unwilling or unable to build an inclusive government.
The new administration led by the head of the constitutional court, Adli Mansour, has said the Brotherhood is welcome to take part in the transition plan mapped out by the army and leading to parliamentary and presidential elections.
It denies that arrests of Brotherhood leaders, including its top strategist and an 84-year-old former head of the movement, amount to a crackdown. The authorities say they are being held on suspicion of committing crimes, including inciting violence.
But the Brotherhood likens it to the darkest chapters in its past, including an army crackdown under Gamal Abdel Nasser in 1954. Its narrative is one of betrayal by a state packed with Hosni Mubarak loyalists who it says sabotaged Mursi's rule.
The Brotherhood fears much worse to come. Not even Mubarak went as far as arresting one of the group's General Guides - the name given to its top leader.
Mehdi Akef, Badie's predecessor in the job, is facing charges of insulting the judiciary and inciting violence.
"It is clear we face a scenario like 1954," said Mohamed El-Beltagi, a Brotherhood politician on the wanted list. He laughs at accusations that he incited violence. "This will not stop at a coup," he said. "It will extend to the dissolution of parties, civil society, the return of the police and military state."
A 50-year-old doctor, Beltagi talked to Reuters behind four lines of Brotherhood security at the sit-in, where he is staffing a makeshift field clinic ready to receive casualties.
Last week, he said he narrowly avoided arrest.
Beltagi has warned that the army's overthrow of Egypt's first freely elected leader will spawn violence, not by the Brotherhood, but by radical elements that it had brought into the mainstream with promises of change through the ballot box.
"We have not and will not resort to violence," he said. But referring to others, he added: "When they see that democracy no longer has results ... They will inevitably be pushed to undemocratic change."
He saw arrests of Brotherhood leaders as designed to sever the movement from its youth base: "It is a deliberate effort to create confusion and force the country into anarchy."
There are already signs that the Brotherhood is struggling to keep the anger in check. Speaking before Monday's violence, Beltagi described the difficulty of dissuading impassioned youths from trying to storm the military facility where Mursi is being held - the very scene of the bloodshed.
"They are putting us under pressure," he said.
Even at the protest camp, there are signs that things are not entirely in control. On Friday, Brotherhood enforcers tried to stop bearded zealots handing out an Islamic text that appeared to draw parallels between today and problems the Prophet Mohammad faced in Mecca with Jews and unbelievers.
For now, Brotherhood leaders will say no more than that they plan to stay in the street until the army restores Mursi to the presidency - a demand detached from reality but seen as part of its short-term strategy for managing the crisis.
In the longer term, the Brotherhood faces critical choices, such as whether to run for office again. If its pragmatism of the past is anything to go by, the tightly knit group will do whatever is necessary to guarantee its survival.
"I suspect they are going to bide their time and head back into the shadows," said Joshua Stacher, a political scientist based at Kent State University in the United States.
"They are far more vulnerable now than at any point under the Mubarak regime. The Mubarak regime never had the power or authority to do what the military is doing to them right now."