Few scenes better illustrate the dilemma facing Palestinian President Mahmoud Abbas than the sight of his West Bank security forces confronting Palestinians enraged by the bloodshed in Gaza.

Israel's air attacks on the poor coastal enclave, prompted, it says, by rocket fire by militants, have killed about 380 Palestinians and wounded 800.

They have provoked violent protests in the occupied West Bank, where Mr Abbas holds sway, and in the Arab world.

Most of the dead have been members of the Islamist Hamas movement, which defeated Mr Abbas's long-dominant, secular Fatah faction in a 2006 election and drove his forces out of the Gaza Strip in a brief conflict 18 months later. Dozens of civilians have also been killed in the Israeli bombardments.

A concerted Israeli campaign against Hamas may sound to some like an opportunity for Mr Abbas, some of whose Fatah loyalists would like to see the Islamist group vanquished so they might regain positions of power there.

However, the Gaza carnage has been anything but favourable for Mr Abbas. Unlike his Hamas rivals, he has the disadvantage of being caught between the competing demands of trying to keep peace with Israel while answering the growing anger and frustrations of his people.

"He's been put in an impossible situation," a senior Western diplomat said. "He has no good options."

Israel, for its part, has tried to make the case that the people of Gaza are tired of Hamas and want Israel to step in. Public support for Hamas may be eroding because of the growing hardships, but few deny its powerful hold on society there.

Mr Abbas sent mixed messages at the start of the crisis. While condemning the air campaign as "criminal", he put the blame on Hamas for provoking Israel by ending a ceasefire and continuing to fire cross-border rockets.

That was in line with Cairo and Washington.

The message was out of touch with many of the Palestinians under fire who see Israel as the guilty party that broke the truce by launching deadly raids and maintaining its blockade of the enclave, said independent member of parliament Mustafa Barghouthi.

"It sounded like he was saying 'I told you so'," a senior European diplomat said. "He didn't consider public opinion."

Two days later, Mr Abbas reached out to Hamas for a "unity" meeting, only to be rebuffed.

Some political analysts say the crisis has made Mr Abbas look indecisive and irrelevant at a time when he is preparing to call for new parliamentary and presidential elections. Few expect the elections to take place soon, given Hamas's opposition.

"The Palestinian people have been left asking, 'Where is he?' 'Where does he stand?'," said Zakaria al-Qaq of al-Quds University.

Mr Abbas aide Saeb Erekat said of the president: "Since the beginning, he began a relentless campaign to stop the attacks in Gaza. That is the only think that he is thinking about."

US and European officials say they are worried about the future of the Western-backed president, who offered peace talks with Israel as an alternative to the violence promoted by Hamas. Whether elections are held or not, no one knows who could succeed him, they say.

Abdullah Abdullah, a senior Fatah official and legislator, said Palestinians committed to peace talks can only lose from Israel's strategy of using force to put pressure on Hamas to stop firing rockets and to agree to a new truce more favourable to the Jewish state.

As the death toll and public anger rose, Mr Abdullah said, "public support for peace will be reduced and Hamas will gain public support outside Palestine and sympathy inside Palestine".

Comments by some West Bank commanders, describing Hamas as the "common enemy" they share with Israel, have further opened Mr Abbas to charges by Islamists of collaboration.

More so than at any time since 1996, when Yasser Arafat cracked down on Hamas in the Gaza Strip, the Western-backed Palestinian Authority's security forces have been on the front line against Islamist groups in the West Bank.

In the city of Hebron, a Hamas stronghold, Mr Abbas's forces shot and wounded three men on Sunday protesting against the Gaza offensive. In Bethlehem, Mr Abbas's men raced to push back protesters throwing fire bombs at an Israeli watchtower.

A Fatah security officer denied his men were cooperating with Israel in suppressing the protests. He said Mr Abbas's men were using force as necessary to prevent violence from spreading.

Mouin Rabbani, an independent Middle East analyst based in Amman, the Jordanian capital, said: "It won't be that difficult for people to put two and two together and to see Israel's campaign in the Gaza Strip and Mr Abbas's campaign in the West Bank as two sides of the same coin."

A senior Fatah official in Gaza described Mr Abbas as someone caught "between two fires - his people and his peace commitments... What a dilemma!"