It was a familiar Israeli reprisal for a Palestinian attack, and another link in the chain of events which makes peace look ever more distant. Tanks and dozens of military vehicles rolled into the West Bank city of Nablus overnight in the largest operation there for weeks, ending with the arrest of 14 suspected militants.The raid was in response to last night’s suicide bombing in Gaza – claimed by Hamas – in which a member of Israel’s internal security service was killed and eight other Israelis were injured. The attack has been interpreted as a challenge to Mahmoud Abbas, the newly elected Palestinian president, who had arrived in Gaza earlier for talks to persuade armed factions to sign up to a ceasefire. Abbas has now ordered Palestinian security forces to deploy at Gaza’s borders with Israel in an effort to stop anti-Israeli attacks. He is under increasing pressure from Ariel Sharon’s government and from Washington to subdue militants. The Israeli prime minister meanwhile paid a rare visit to troops in northern Gaza to impress on them the need to stop Palestinian rocket and mortar attacks on Jewish settlements.