“I am very suspicious of Brussels,” U.K. Prime Minister David Cameron said in January.

The feeling is mutual.

Seventy-seven leading European and American policymakers in POLITICO’s Caucus expressed deep misgivings about the prime minister’s attempt to win new terms for U.K. membership of the EU, and faulted him for mishandling the negotiations.

“He seems to think that when he’s at home, no one in Europe hears what he says!” said one Caucus participant.

More than a few European members of the Caucus didn’t get Cameron’s political rationale in promising a referendum on EU membership in the first place, seeing it as a lose-lose for him. “If the U.K. remains in the EU, he will have to face internal challenges” in a still broadly Euroskeptic Tory Party, one said. “If the U.K. leaves the EU, he will have to face the consequences of a potential economic downturn.”

Participants in the POLITICO Caucus — including the Italian, Czech and Turkish ambassadors to the EU, NATO Deputy Secretary-General Alexander Vershbow, former EU competition commissioner Joaquín Almunia, European Council President Donald Tusk’s chief foreign policy adviser, and other high-ranking officials from the EU institutions — spoke freely on condition of anonymity

Twenty-one percent of the Caucus rated Cameron’s performance to date as poor, and 41 percent called it average.

Missed opportunity

Behind the verdict on Cameron’s diplomacy was dismay at a “short-term decision taken to solve short-term internal party upheaval” by “asking for things that do not make the EU any better.”

Back in early 2015 Cameron’s manifesto promised to “reform the workings of the EU” which he described as “too big, too bossy and too bureaucratic.”

“He could have asked for some real improvements in terms of democratic accountability, bringing Brussels politics out of the back-rooms,” lamented one Caucus participant.

But when he outlined his position in a letter to Tusk in November, Cameron focused his demands on four relatively narrow “baskets” of reform: economic governance, competitiveness, sovereignty and migration. An undertaking to cut red tape for business proved relatively simple, and sovereignty and governance concerns are already largely covered by existing treaties but could be clarified, Brussels said. Most diplomatic wrangling has centered on Cameron’s attempt to ban EU migrants from receiving in-work benefits for four years. In the end, leaders will discuss a proposed “safeguard mechanism” which would allow the U.K. to limit in-work migrant benefits for the same period, providing the European Commission and Council agree it is necessary.

More than two thirds of Caucus members thought the hard-fought “safeguard mechanism” would make little difference to the number of people who move to Britain.

“The real ‘draw factor’ is the British economy, not the benefit system,” said one participant, echoing the view of migration experts. “People come to the U.K. to work, not live in poverty.”

“He is not doing a bad job with the concrete renegotiations,” was one more favorable assessment. “But he had maneuvered himself into a very difficult situation in the years before.”

Disintegration Now

The wider fear among Caucus members was that a British departure would hit the bloc at an existentially vulnerable moment. The migration crisis, continued economic woes of the eurozone and the growing strength of extremist parties all raise questions about the future of open borders, free trade and the viability of the EU itself.

“Brexit will encourage nationalistic attitudes in other member states,” one warned. Another said it would “feed those forces inside and outside the EU that promote disintegration.”

Worse for Cameron, Scots are overwhelmingly in favor of remaining in the EU, leading some to speculate that a Brexit would re-open the question of Scottish independence that he thought he’d put to bed last year.

“Scotland will go first, but Northern Ireland may soon be close behind,” said one Caucus member, “because even Unionists know how good the EU has been to them.”

Unionist parties in Northern Ireland have so far remained silent on the implications of a Brexit for the province. Northern Ireland’s economy is intimately linked to the Republic of Ireland, an enthusiastic EU member that’s in the eurozone.

A not-so-special relationship

Caucus members generally agreed that any sign that integration was “reversible” would weaken both Europe and Britain, but they were in little doubt that the latter would suffer more.

“Alone it will be weaker,” one said. “It can either follow the EU line, or find that things go the EU’s way in spite of the U.K.’s views.”

That could even be a boon for Europe, some predicted, arguing: “We would soon see a power shift from London to the Continent, thus strengthening the EU-U.S. relationship.”

In any event, “the U.S. prefer to have a single European interlocutor for the big issues” one said, and another added: “The U.S. counts more on Germany these days.”

Many pointed out that Britain will remain in NATO, the Continent’s main military alliance. However, one participant said “ ‘never closer union’ weakens Europe’s role in peacekeeping, which is particularly useful for Russia. Dividing Europe is one of its primary goals.”

“Underneath the U.K.’s foreign affairs standing is its clout in trade and financial matters,” said a Caucus participant. “This weight would take a considerable hit outside of the European context — particularly bearing in mind that half of the U.K.’s trade is with Europe.”

“The so-called ‘special relationship’ with the U.S., if it ever existed, has gone,” another said. “The U.S. say officially at the highest level that they are only interested in the U.K. in so far as they are part of the EU. The U.K. has the illusion of being a great power — not anymore.”

To see a full list of participants in the POLITICO Caucus click here.

Emmet Livingstone contributed reporting.