Say an Obama State of the Union address is expected to question American trade relationships. Imagine, then, David Cameron placing a stern call to the president beforehand, insisting the UK "values a strong US in a strong Nafta". This on the heels of a British minister having asserted paternalistically that America must remain in Nafta and must prevent American voters from having a choice in the matter if only because this policy course is "in the British interest".

Now, there's no point being naive about asymmetrical power dynamics, so the prospect of any UK politician bullying an American president to pursue a particular domestic agenda solely in concern for "the British interest" is clearly farcical. Nevertheless, the Obama administration's pouring cold water on Cameron's plans for an In/Out referendum on UK membership of the EU bespeaks an old-style imperialism unbefitting a modern Democratic president. UK to US: butt out.

On Joe Biden's London visit in February, the Vice President may have conveniently echoed Cameron's own desire for Britain to remain in the EU, but the voice of support comes at a cost. This unambiguously selfish concern for "a strong UK in a strong EU" implies that America primarily values the UK as an obedient proxy in the larger, more important body of the EU — thus evoking all those tired, unfortunate metaphors about yappy breeds of dog.

Yet what's most striking about that Nafta analogy is its staggering inadequacy. In fact, it's a terrible analogy, though I challenge you to find another one that works. The US is not a member of any alliance remotely equivalent to the EU, making it pretty rich for Washington to compel Britons to remain under its heel. The US dominates Nato, and has often regarded WTO obligations as mere suggestions. America enjoys a veto in the UN Security Council, and has blithely opted out of the International Criminal Court. The US surrenders its sovereignty unconditionally to no higher power, and Americans would be outraged were the majority of their laws drafted in Mexico, Quebec, or Guatemala.

Yet among American liberals, about the EU one cannot utter a discouraging word. Right-on Yanks perceive the EU as a beacon of benevolence, an icon of peace, fairness, and equality. This laudable diet of the kind, the rational, and the wise presides over a utopia to which in fantasy left-wing Americans retire. Criticising the EU in these circles is like drawing horns on Nelson Mandela, or making lewd thrusting hand gestures at Aung San Suu Kyi.