It is not often that Europe has the chance to play a pivotal role on the world stage. But as the Palestinians push for recognition as a state at the United Nations later this month, the European Union is finding itself courted by each side, and therefore more influential on the Middle East process than at any time since the Oslo Accords.

As ever, the biggest challenge facing the E.U.’s 27 member states is presenting a unified front. There are 10 compelling reasons for them to coalesce around a “yes” vote and keep the two-state approach to Middle East peace alive.

The critical vote is likely to be in the General Assembly, on a resolution to upgrade the Palestinians’ status from observer to non-member state. The Palestinians are likely to get a majority, but what matters more than the outcome of the vote is its size and composition.

The Israeli government is lobbying hard for a “no,” and the P.L.O., unable to significantly shape realities on the ground, hopes to at least show some diplomatic traction for its continued faith in the two-state approach. Europeans find themselves in the unusual position of being the key prize in this tussle.