The political and territorial challenges facing Israeli and Palestinian peace negotiators are formidable and familiar. The economic obstacles to the creation of a viable Palestinian state are also formidable, but easier to make a dent in — if all the donors who claim to care about the Palestinians and peace live up to their promises.

On paper, this week’s international pledging conference was a huge success. Led by the US, the EU and Saudi Arabia, donors committed to contribute $7.4 billion over the next three years. That is almost $2 billion more than the Palestinian Authority had sought, though probably less than it really needs. Things got even tougher after the West suspended most of its support following Hamas’s 2006 election victory. It is crucial that the people of Gaza also receive support.

Much of the money pledged will be needed just to keep Abbas’s government solvent. What the Palestinian economy really needs is private investment to reanimate commerce and revive trade with the world. That can only happen once Israel agrees to remove the barricades that seal off West Bank communities from each other and feels secure enough to ease the passage of goods through border crossing points. To make a real difference, the billions pledged in Paris will need to be matched by diplomatic progress.