INSIGHT-Mursi's overthrow rattles Egypt's Islamists in their heartland
* Mursi's supporters call overthrow an illegitimate coup
* Islamist groups formed political parties after 2011 revolt
* Analysts see defining moment for political Islam in Egypt
ASSIUT, Egypt, July 19 (Reuters) - You can trace the aspirations and disappointments of Egypt's revolution across the walls of the southern city of Assiut.
The most faded graffiti lambasts Hosni Mubarak, the autocrat who ruled for three decades until a 2011 uprising toppled him. More recent daubings take on his successors: a council of military generals and civilian president Mohamed Mursi.
Additions since the army overthrew Mursi this month attest a new wave of anger - this time from Islamists who feel cheated by his fall. "Egypt is Islamic, no matter what the Christians think," one reads. Another calls the army chief "a dog".
Assiut offers a window into what the future might hold for Egypt's Islamists, who have dominated election after election since the 2011 revolt and, until Mursi's ouster, constituted a commanding and ever more vocal force in Egyptian public life.
The poor, conservative region along the Nile has for decades been a stronghold for both radical and moderate Islamists, who have cemented their influence by delivering basic services in areas where the central government has historically been aloof.
The goodwill and logistics networks built up by those groups over decades - particularly Mursi's Muslim Brotherhood - helped win them political sway in the aftermath of Mubarak's fall.
But even the Islamists' heartlands have not been immune to the distrust and suspicion that has grown among many Egyptians during the past year over what they saw as the Brotherhood's ineffective and divisive rule.
The headquarters of the Brotherhood's political wing - which took about half the area's parliament seats - was sacked and looted this month. The governor Mursi appointed has not come to his office for weeks since protesters blocked him from entering.
The blow has inspired a mix of anger, defiance, fear and denial among Islamists in Egypt's south. But their history and heavy presence in the impoverished region also offers an insight into how they might work their way back into political life.
"The lesson for us has been to interact with the street more and more. That's all," said Mohamed Senussi, an official in the Assiut branch of the Brotherhood's Freedom and Justice Party.
"Your most basic power is in the streets."
Assiut's poverty is palpable outside the provincial capital. Farmers ride donkey carts through fields and harvest crops by hand. A huge cement factory run by Mexico's Cemex is one of the few obvious intrusions of an industrialised global economy.
Despite its marginalisation, the region has contributed two figures central to the struggle between Islamists and the army that has defined much of modern Egypt's politics: Gamal Abdel Nasser and Sayyid Qutb.
Qutb, a founder of Islamist thought and Brotherhood leader, backed Nasser and his "Free Officers" when they toppled Egypt's monarchy in 1952. Nasser soon turned on the Islamists, imprisoning thousands, and eventually had Qutb executed.
Islamist groups were rejuvenated under Nasser's successor Anwar Sadat and were able to expand their influence particularly in poor areas like Assiut, which became a base for the most radical and militant offshoots.
"The alternative for these societies is or used to be the Islamic movements, who could provide them with these services," said Khalil al-Anani, an expert on political Islam at Britain's Durham University.
"They tried to fill the gap of the absence of the state."
Islamists' influence and organisational strength won them a dominant voice in post-Mubarak Egypt. The Freedom and Justice Party and the ultra-conservative Nour Party won big majorities in parliament, and the Brotherhood was able to push through a contentious constitution.
The military's overthrow of Mursi swept away those victories. The army-backed interim cabinet formed this week did not include a single member of either party, parliament has been dissolved and the constitution suspended.
Anani said Mursi's fall had brought the Islamists to a defining moment. They could end up like their Algerian counterparts, who became fractured and violent after the army cancelled their election wins in 1992.
Or they could follow Turkey's example, where Islamists regrouped, reformed and won elections after the military pushed them from power in 1997.
"You will always have political Islam," Anani said. "But we don't know what it will be - which version, the progressive one, the aggressive one, the violent one, the moderate one?"
GUNS AND VOTES
Men with the long beards of strict Salafist Muslims gather nightly for prayers at Assiut's Abu Bakr al-Siddiq mosque, a hub for Al-Gamaa Al-Islamiya, a former militant group that later gave up violence and entered mainstream politics.
Gamaa Islamiya, which was founded in Assiut, has been a testament to the ultra-conservative Salafist movement's emergence into the light since Mubarak's overthrow.
Back in the 1990s, the group waged a bloody campaign against security forces with the aim of creating an Islamic state. Police levelled entire sugar cane fields where the militants hid to flush them from their southern Egyptian strongholds.
After hundreds of deaths and thousands of arrests, the rebellion crumbled. The group eventually renounced violence and still maintains significant influence in southern Egypt through its preaching and charity networks and political party.
Mursi's overthrow has put Gamaa Islamiya in the spotlight again - this time over the question of whether Egypt could see a reprise of the violence that wracked it under two decades ago.
So far the group has thrown its weight behind peaceful protests and vigils calling for Mursi's reinstatement and has loudly and repeatedly disavowed violence.
Gamaa Islamiya's spiritual leader, Abdel Akhir Hammad, said the group had learned its lesson in the 1990s. Still, that did not mean young members of other groups would be as restrained.
"One of the reasons that made Gamaa Islamiya youth take up arms in the past was a loss of hope," he said in an interview in his sparse office in an annex of the Assiut mosque.
"When the pressure and arrests of the group's leaders increased, the youth were swept up by violent currents. We don't want Egypt to go back to this again."
The crisis would only really be resolved with Mursi's restoration and a return to the legitimacy of the ballot box, Hammad said. Until then, political factions would squabble, and stability would be elusive.
"If we haven't returned to legitimacy, reconciliation would be like a wound you haven't cleaned and then you closed and bandaged. You need to clean it first, and this cleansing is the return of legitimacy."
LOSS OF TRUST
Assiut is also a microcosm of Egypt's religious diversity, which critics frequently accused Islamists, led by the Brotherhood, of neglecting after they took power.
Although official statistics do not exist, about a quarter of the province's roughly 4.5 million people are believed to be Coptic Christian, compared with about 10 percent of the country.
It is not unusual to see Christians out shopping and, within the confines of church compounds, eating before nightfall during Ramadan, when many Muslims fast during daylight.
Louqa, a monk and church leader in Assiut, said he was surprised at the turnout the socially and religiously conservative city saw during the protests against Mursi in the days before the army ousted him.
He recalled meeting men and women of all ages headed to the demonstrations. "This was a clear mark of discontent with the general situation in the country and with the ruling policies during the recent period," he said.
The problem had been "bigger than Dr. Mursi", Louqa said, pointing to conflicts that arose between Islamist movements and groups like the media, judiciary and artists who wanted a "civilian state" - a term often used in Egypt, where "secular" is seen by many as derogatory.
The loss of faith in Islamist leaders was not necessarily due to their ideology, he said. Christians, for instance, had been living with Muslims for centuries and knew Islamist movements were not going away.
"Egyptians are pious by nature, both Christians and Muslims. If they see religious leaders working effectively in society, they will certainly rally around them," Louqa said.
But if they fail to live up to their expectations, he added, "the shock will be severe".
WHITHER THE BROTHERHOOD?
For now, the Brotherhood is firmly on the back foot. Senior leaders have been arrested, sympathetic television channels shut down, and state media has enthusiastically returned to its old role of demonising the movement.
But in Assiut it is hard to find Brotherhood members willing to speculate about what the group will do if Mursi does not return. Ashraf Hussein, the Brotherhood's local spokesman, looked affronted when the question was put to him.
"He'll come back. Who said he wouldn't come back? The people want him back," he said. "The people want to preserve the gains of their revolution. And they are coming out to the streets."
Recounting the Brotherhood's 85-year history providing services and standing against authoritarian government, Hussein said the group's popularity would only grow as people came to see the "obstacles and conspiracies" that confronted it.
"I am unable to imagine that the dictatorial regime can come back again. It's over, it's finished," he said.
A few are more contemplative. Mohamed Askalany, a 63-year-old member of the Brotherhood's political party, was willing to acknowledge the possibility Mursi would not return.
Stressing that he was speaking only about his personal views, he said he believed the party should participate in elections even if the president did not come back.
"It should not isolate itself from politics," Askalany said. "And it should not isolate itself from the Egyptian street."
(Additional reporting by Muhammad Yamany; Writing by Alexander Dziadosz; Editing by Will Waterman)