On one occasion, at an EU summit press conference which continued until well after midnight, I remember seeing Javier Solana nod off on the platform next to Angela Merkel. When she finally passed him the microphone, he did not know what was happening, and fell back on telling stories, before finally saying "enough is enough." A few days ago in an interview with the Spanish daily ABC, he used the "enough" word again — "It's time to go. Ten years is more than enough" — and confirmed that he would not be seeking a further mandate. Officially, he will be leaving in October, but everyone is already wondering who will be the "new" Solana.

For diplomats, journalists, and EU political analysts, Spain's Solana is not just a former foreign minister, an ex-general secretary of NATO, or the current coordinator of EU foreign policy — he is the "so-called head" of Europe's "so-called diplomatic service." That may sound like a lot of "so-calleds," and it certainly is. But bear in mind that in the field of EU foreign policy, many things remain on the level of "so-called" — not least, our so-called embassies, so-called unity, and so-called firmness — while real diplomacy is conducted by EU member states, who jealously guard their territory. Throughout his ten-year tenure, Solana has proved to be a skillful navigator of the world of "so-called" diplomacy, making his mark as the face and the ears of the Union, and even — as we saw with the Iranian nuclear programme — its negotiator. And, there is no denying the enormous amount of work he has contributed as Europe's tireless emissary. In a decade of service to the Union, he must have spent two years on planes — putting out fires in the Balkans, and in the Middle East, and keeping alive hopes for a meaningful European commitment in unstable regions of the world.

When speaking on behalf of the EU, Solana had to make do with a very limited mandate, which meant that he could neither promise, nor indeed do very much. He had the backing of a large bloc, but one that was divided, and in terms of foreign policy, entrenched behind the US. At the same time, he also had to weather the hot breath of the European powers — like France, Germany, and the UK — who did not want a competitor in Brussels. For these reasons, Solana will be remembered as a diplomat given to breezy declarations of intent, who was often evasive and tended to resort to empty diplomatic jargon. It is therefore not surprising that it was President Nicolas Sarkozy, and not Solana, who succeeded in engineering the 2008 peace negotiations that brought an end to the fighting between Georgia and Russia. However, it is important to acknowledge that there was nothing innate about Solana's weakness, which was inherent in his mandate as High Representative for the Common Foreign and Security Policy. Even the sound of this long and tortuous title could not fail to act like a sedative on his foreign counterparts. In short, the Union has had the Solana that it deserves — and in spite of everything, I think he has more than succeeded in fulfilling the modest ambitions of the role that he was assigned.

On the issue of his future replacement — whether it be Swedish Foreign Affairs Minister Carl Bildt, or the outgoing head of NATO Jaap de Hoop Scheffer, or anyone else for that matter — it is safe to say that the "new" Solana will have more impact, at least in theory. Once the Lisbon Treaty comes into force, the High Representative for Common Foreign Policy will also be the Vice-President of the European Commission, and the issue of a dual mandate from the European Commission and the European Council, of which Solana was the Secretary General, will have been settled. The "new" Solana will also have the benefit of presiding over a network of embassies (which are currently known as "Commission delegations") and several hundred diplomats. The only problem is that member states are still not ready to build a truly common foreign policy and surrender representation of their national interests to European diplomacy. So the "new" Solana will have to continue pretending that he can achieve more than he has been empowered to achieve, or alternatively, he or she will be forced to shake up the current status quo, and risk the ire of Paris, London and Berlin.