* Abbas allows protesters to march on Israeli checkpoints
* Some Palestinians say third Intifada (uprising) brewing
* West Bank protests hinge on developments in Gaza
By Ali Sawafta
RAMALLAH, West Bank, July 27 (Reuters) - While the Gaza Strip burns, the occupied West Bank is smoldering, with violent clashes between Palestinians and Israeli forces raising the spectre of a new popular uprising after years of relative calm.
In just a three-day period late last week, 10 Palestinians died and some 600 wounded during a spate of angry protests against the prolonged military offensive in nearby Gaza.
On Sunday, Israeli police said they foiled a potentially deadly attack when they stopped a car laden with explosives as its driver tried to reach Israel via a West Bank checkpoint, while riots broke out once more overnight in East Jerusalem.
In normal times, such friction would be dominating local headlines, but with all eyes fixed instead on Gaza, where more than 1,050 Palestinians have died so far in 20 days of fighting, the growing tension has been largely overlooked.
If the Gaza bloodshed continues for much longer, Palestinians say, it might prove impossible for Israel or Western-backed Palestinian President Mahmoud Abbas to keep the lid on growing rage in the West Bank.
"It's premature to describe what's happening as an uprising, (however) the Palestinians have overcome their fear and are pushing towards the Israeli checkpoints," said Hani al-Masri, a political analyst in Ramallah, the de-facto Palestinian capital which lies just to the north of Jerusalem.
More than 10,000 Palestinians marched on the Qalandia checkpoint outside Ramallah on Thursday night, the largest such rally in years, with whole families joining the demonstration.
"To Jerusalem we go, martyrs in the millions!" the crowds chanted. "Our souls and our blood we sacrifice for you, Gaza!"
In the ensuing confrontations, youths hurled stones and aimed screeching fireworks at Israeli soldiers, who shot back with rubber and live bullets, killing a 17-year old and injuring dozens, said Palestinian medics who treated the wounded.
Israel captured East Jerusalem, Gaza and the West Bank in a 1967 war. It has annexed East Jerusalem, pulled its settlers and soldiers from Gaza in 2005 and offered limited self rule to Palestinians in the West Bank while rapidly expanding its network of Jewish settlements in the kidney-shaped territory.
Palestinians want an independent state in Gaza and the West Bank, with East Jerusalem as their capital.
Repeated U.S.-led negotiations over the past 20 years have failed to broker a permanent deal. The most recent round of direct talks collapsed in April, with Palestinians livid over more settlement building and Israelis furious that Abbas had signed a unity pact with the Hamas Islamists in Gaza.
The lack of any imminent solution to the decades-old Middle East conflict, coupled with a worsening economic outlook for Abbas's aid-dependent Palestinian Authority, have fueled the anger in a West Bank already on edge even before Gaza exploded.
In June, following the murder of three Jewish teenagers, Israeli forces arrested hundreds of people across the territory in its search for suspects. Israel blamed Hamas, but the group neither denied nor acknowledged responsibility for the killings.
"The Intifada of the people has begun," said Walid Saqr, a taxi driver in his 50s, using the Arabic term for uprising.
"They've given us no other choice with the poverty and unemployment around us. The Intifada is coming, and there's no place for those who say 'give it a little time, things might get better'. Man, since we were all little, nothing has changed!"
Palestinians have already staged two Intifadas.
The first ran from 1987 to 1993 and led the way to the Oslo peace accords between Israel and the Palestine Liberation Organization (PLO), ushering in a period of hope and expectation that barely outlived the decade.
The Second Intifada broke out in 2000 after the failure of a U.S.-led drive to negotiate a final peace settlement. Over the following seven years, more than 1,000 Israelis died, half of them in suicide attacks mostly against civilians, and more than 4,500 Palestinians were killed by Israeli forces.
The Palestinians lost ground in the court of world opinion as a result and their appetite for resistance was curtailed.
Abbas himself has vowed never to let another uprising take hold, saying it would spell fresh ruin for his people, but this latest Gaza violence has left him in a vulnerable position.
A long-time foe of Hamas, which chased his forces out of Gaza in a brief civil war in 2007, Abbas has nonetheless clearly backed the Islamist militants in this latest struggle and has adopted as his own their demands for a permanent ceasefire.
His inner circle have also been virulent in their verbal attacks on Israel. "Gaza is the steadfast shield in the face of the fascism, racism and terrorism of (Israel)," said senior PLO official and Abbas confidant Yasser Abed Rabbo.
Abbas's own security forces, lambasted by many Palestinians for cooperating with the Israeli army in the West Bank, have taken the unusual step of letting protesters march on Israeli checkpoints and not trying to stop them, as they previously did.
"The current leadership is trying to ride this wave and embrace the call for demonstrations," said analyst Masri.
Israel in turn appears to be responding to the protests with an uncompromising show of force, using a significant amount of live fire, perhaps hoping to scare people off the streets.
The army says it only uses live ammunition when the life of its soldiers is in danger, adding that it was investigating the recent West Bank killings, including those of three teenagers.
Israeli security forces are also facing nightly protests in mainly Arab districts of East Jerusalem, rocket-strewn streets bearing witness to the violence when dawn comes.
A Palestinian teenager was abducted from the streets of Jerusalem earlier this month and burnt alive, in an apparent revenge attack for the killing of the Jewish teens. Three Israelis have been arrested and are awaiting trial.
Two Palestinians were badly beaten in the city overnight on Sunday in a suspected "nationalist" attack by Jewish youths.
Despite the undoubted turbulence, Palestinians said the recent confrontations were largely unplanned and spontaneous, with none of the major political groups in the West Bank looking to organise a structured campaign against Israel.
"The Palestinian Authority has made a political decision to allow people to reach the points of friction with the occupation army, but these confrontations don't have any staying power," said Ali Saleh, a 30-year old public sector worker in Ramallah.
"It's linked to the situation in Gaza, and if that quietens down, it will get calm here too." (Writing by Crispian Balmer; Editing by Gareth Jones)