* Mursi's opponents call protests to mark anniversary
* Grievances include constitution
* Brotherhood launches campaign to help poor
By Tom Perry
CAIRO, Jan 24 (Reuters) - Egypt marks the second anniversary of the uprising that swept Hosni Mubarak from power with little to celebrate. Deeply divided and facing an economic crisis, the nation is bracing for more protests, but this time against a freely elected leader.
President Mohamed Mursi's opponents plan to march to Tahrir Square on Friday to vent anger at the new Islamist leader and his Muslim Brotherhood backers, whom they accuse of betraying the goals of the Jan. 25 revolution that galvanised Egyptians in a display of national unity that has not been seen since.
"We don't see it as a celebration. This will be a new revolutionary wave that will show the Brotherhood that they are not alone - that there are other forces that can stand against them," said Ahmed Maher, founder of the April 6 - a group that helped ignite the uprising by using social media to organise.
The Brotherhood has said it will not send its supporters to Tahrir Square on Friday - a decision that at least limits the scope for more of the unrest that has compounded Egypt's economic troubles.
Instead, with its eye on forthcoming parliamentary polls, the electorially savvy Brotherhood is marking the anniversary with a campaign to help the poor. With allies, it promises to send volunteers to renovate 2,000 schools, plant trees, deliver medical aid and open "charity markets" selling affordable food.
"The importance of the anniversary is to lift the spirits of the Egyptian people: more hope and more work," said Ahmed Aref, a Muslim Brotherhood spokesman who was in Tahrir Square for the entire 18-day uprising against Mubarak.
Inspired by Tunisia's uprising against President Zine al-Abidine Ben Ali, Egypt's revolution helped set off more revolts in Libya and Syria. It brought political freedom that allowed the dramatic rise to power of the Brotherhood, an Islamist group that was outlawed under decades of army-backed autocracy.
Two years on, Egypt is struggling with a deep economic crisis caused by political turbulence which has continued unabated since the election of a new president.
The sense of common purpose that united Egyptians against Mubarak has given way to conflict. Secularists and liberals accuse the Muslim Brotherhood of seeking to dominate the country. The Islamists say their opponents are not respecting the rules of the democratic game.
Mursi's bid to fast-track a controversial, Islamist-tinged constitution in December fuelled days of protests that helped send the Egyptian pound to record lows against the U.S. dollar. Analysts fear Friday could bring more yet more trouble.
"I foresee very big protests, and some civil unrest," said Elijah Zarwan of the European Council on Foreign Relations. "Two years on, a real sense of disenchantment has settled on Egypt.
"There is a fairly widespread sense that the country is slipping, socially, economically and in terms of governance. Politically, the divisions have become so fierce that it's hard to imagine the various parties and factions coming to an agreement, even on the things they agree on."
CONSTITUTION "NOT WORTHY" OF REVOLUTION
Despite winning approval in a popular referendum, the new constitution remains one of the main grievances of the array of leftist and liberal parties calling for Friday's protests.
"Nothing will undermine our hopes, but this constitution is not worthy of the revolution," Maher of April 6 told Reuters.
Its critics say the constitution offers inadequate protection for human rights, gives the president too many privileges and fails to curb the power of the military establishment.
Mursi's supporters say the criticism is unfair, enacting the constitution quickly was crucial to restoring stability, and the opposition is making the situation worse by perpetuating unrest. The referendum, they say, settled the issue democratically, and protests are just another chance to stir up trouble.
Both sides trade blame for economic hardship as the falling currency drives up the cost of imported food on which the mostly desert nation depends. The opposition says government economic mismanagement is at fault, while the government blames the climate of instability fomented by its opponents.
Other sources of friction abound. Activists are impatient for justice for the victims of political violence perpetrated over the last two years. Little has been done to reform brutal Mubarak-era security agencies. A spate of transport disasters on roads and railways neglected for years is feeding discontent.
The political polarisation is making it harder for the Mursi administration to address the economic problems. In December, he postponed reforms needed to address a gaping budget deficit and secure a $4.8 billion loan from the International Monetary Fund.
With its foreign currency reserves critically low, the finances of the Arab world's most populous nation have been propped up by the tiny but rich Gulf emirate of Qatar, which has supplied some $5 billion in grants and loans.
The Brotherhood acknowledges that many of the revolution's goals have yet to be realised. Yet the group sees major achievements including the new constitution and the election of the country's first civilian head of state.
Marking the anniversary with a big charity campaign is a classic Brotherhood tactic, demonstrating the populist impulses and organisational muscle that have swept the Islamists to five straight election victories since Mubarak fell - two for parliament, one for president and two referendums.
"The people are interested in their daily bread. Citizens want to feel the change brought by the Egyptian revolution. This requires the opposition to translate what they are calling for into real policy programmes," said Ahmed Subei, a spokesman for the Brotherhood's Freedom and Justice Party.