MOSUL, Iraq (Reuters) - A jihadist message, "Islamic State endures", is still graffitied on the front gate of Thanoun Yahya, an Iraqi Christian from the northern city of Mosul, scrawled by Islamist militants who occupied his home for three years when they ruled the city.
He refuses to remove it, partly in defiance of the militants who were eventually beaten by Iraqi forces, but also as a reminder that Iraq's scattered and dwindling Christian community still lives a precarious existence.
"They're gone, they can't hurt us," said the 59-year-old, sitting in his home which he reclaimed when Islamic State was driven out in 2017. "But there aren't many of us left. The younger generation want to leave."
The stark choice facing many Christians in Muslim-majority Iraq will be highlighted during the first ever papal visit to the Biblical nation. Pope Francis's trip runs from March 5-8 and will include a stop in Mosul.
Yahya sold the family's metalwork shop to pay a ransom for his brother, kidnapped by al Qaeda militants in 2004 at a time when Christians were being abducted and executed.
Since then, he has watched siblings leave for foreign countries and work and income dry up.
Of 20 relatives who once lived in the neighbourhood, only his family of six remain.
Iraq's Christians have endured unrest over centuries, but a mass exodus began after the U.S.-led invasion of Iraq in 2003 and accelerated during the reign of Islamic State, which brutalised minorities and Muslims alike.
Hundreds of thousands left for nearby areas and Western countries.
Across Iraq's northern Nineveh Plains, home to some of the oldest churches and monasteries in the world, the remaining Christians often live displaced in villages that fell easily to Islamic State in 2014 or in enclaves of bigger cities such as Mosul and the nearby self-run Kurdish region.
The Islamists' rule over almost a third of Iraq, with Mosul as their capital, ended in 2017 in a destructive battle with security forces.
'ONLY GOD CAN HELP'
Physical and economic ruin remain. Iraqi authorities have struggled to rebuild areas decimated by war, and armed groups that the government has not been able to control vie for territory and resources, including Christian heartlands.
Christians say they are left with a dilemma - whether to return to damaged homes, resettle inside Iraq or migrate from a country that experience has shown cannot protect them.
"In 2014, Christians thought their displacement would last a few days," said Cardinal Louis Sako, head of Iraq's Chaldean Catholic Church.
"It lasted three years. Many lost hope and migrated. There's no security or stability."
Iraq's indigenous Christians are estimated to number around 300,000, a fifth of the 1.5 million who lived in the country before the 2003 invasion that toppled Sunni Muslim leader Saddam Hussein.
Christians were tolerated under Hussein, but singled out for kidnappings and killings in the communal bloodshed of the mid-2000s onwards.
Pope Francis is to visit Iraq on an historic trip that eluded his predecessors. He will say a prayer for the victims of conflict at a site in Mosul where old churches lie in ruins, once used as religious tribunals by Islamic State.
Christians welcome the visit, but do not believe it will improve their lot.
"The pope can't help us, only God can," Yahya said.
Yahya's family, who fled to Iraq's northern Kurdistan region during Islamic State's rule, is one of just a few dozen that have returned to Mosul out of an original population of some 50,000 Christians, according to local clergy.
His two teenage sons help out at the local church, the only one fully repaired in Mosul, which fills to about half its modest capacity on Sundays.
Firas, his eldest, finds little more than a day a week of casual labour and sees no future in Mosul, Iraq's second-largest city.
"If I want to marry, I'll have to leave. Christian women from here are displaced to other areas and don't want to come back," he said. "Ideally, I'd go to the West."
The experience of Islamic State, which told Christians to convert, pay a tax or be killed, and the inability of Iraqi and Kurdish security forces to prevent the group marauding through their hometowns, has left many Christians distrustful of any but their own.
The nearby Christian town of Hamdaniya boasts its own militia, which local officials say is necessary because of the proliferation of Shi'ite Muslim paramilitary groups which seek control of land, and Islamic State militants who remain in hideouts across northern Iraq.
"If there were no Christian militia here, no one would come back. Why should we rely on outside forces to protect us?" said a local militia leader, who requested anonymity.
Nearly 30,000 Christians, half of Hamdaniya's population, have returned, including a small number from abroad, and began rebuilding infrastructure thanks to foreign aid. It is a rare bright spot.
In the neighbouring village, Christian leader Sako said most Christians were unable or unwilling to return out of fear of a local Shi'ite militia, and because non-Christians had bought their property in their absence.
Some have showed interest in resettling in Hamdaniya, but local officials generally reject this, fearing it would weaken Iraqi Christians' presence.
"If people move here from their own villages, it empties those areas of Christians," said Isam Daaboul, the mayor of Hamdaniya.
"This threatens our existence in areas we've been for generations."
(Reporting by John Davison; Editing by Mike Collett-White)