They see themselves as the great defenders of British sovereignty against the political ambitions of our continental partners.

Yet those same people remain largely silent over the transfer of British sovereignty in crucial areas of national security to the United States.

In a three-paragraph written statement slipped out in July, just one day before Parliament rose – and almost completely unnoticed by the press – the Defence Secretary announced that the Government is permitting the US administration to install additional equipment at Menwith Hill, in Yorkshire, to support its unproven missile defence system.

There has been no public debate in Britain about the desirability, or workability of missile defence, let alone about the strategic assumptions that underpin it. The American programme has suffered from successive test failures and critical Congressional reports over the past 20 years.

The political will to persevere with it has been driven as much by industrial as military priorities. Its original justification was to defend America against China; now it is said that it will protect against Iran, depicted in Washington as an implacable, long-term enemy.

Des Browne's statement swallows the neo-conservative terminology of the Republican right, declaring that "the Government welcomes US plans… to address the growing threat from rogue states".

Even Tony Blair hesitated to apply the label of "rogue state" to all those the Bush Administration labelled as beyond the limits of international diplomacy.

Commendably, the Blair Government worked with the US and others to bring Libya back within acceptable rules of international order.

After several years of hardline rhetoric against North Korea – the world's clearest example of a state run by people who reject the norms of civilised behaviour both towards their neighbours and towards their own citizens – the Bush Administration is not only negotiating with them but even offering economic assistance in return for co-operation.

While attacking Iran, a signatory of the Nuclear Non-Proliferation Treaty, for falling short of its treaty obligations, Washington is offering non-signatory India a nuclear partnership which some say threatens to undermine the entire non-proliferation regime.

The exceptional depth of American hostility towards Iran is rooted in the ideology of a "long war" between the West and Islam, in which Iran has now replaced Iraq as the prime sponsor of anti-Western terrorism and Islamic fundamentalism. The US approach to the complex international politics of the Middle East is mistaken. The British government should resist aligning this country with that approach.

Those in power in Iran are hardline nationalists with deeply unattractive views and close links to Hezbollah and Hamas, but they are effective at exploiting Anglo-Saxon hostility to bolster their position against domestic critics.

Without some co-operation with Iran, the restoration of stable government in southern Afghanistan will prove impossible; the Iranian government has, after all, assisted efforts to contain the Taliban at crucial points over the past five years.

The current drift of US Iraq policy towards supporting Sunnis against Shias, and bolstering Saudi and Israeli national interests, does not provide a short-cut towards a stable
Middle East region. Britain's invitation to the Saudi king
to make a state visit this
autumn signals support for the US-Saudi alliance in the Middle East, as well as commitment to BAE's biggest arms export customer. Liberal Democrats will press the Government to challenge their guests on Saudi support for Sunni fundamentalism; the evidence on suicide bombers and al-Qaida terrorists in Iraq, for example, suggests that many more have crossed the Saudi frontier than have entered from Iran.

Meanwhile, our government allows the continuation of American enclaves on British soil, protected from Parliamentary scrutiny or public debate. Menwith Hill is effectively outside the control of British authorities, with Ministry of Defence police patrolling only the outside perimeter.

In the months after the 9/11 attacks of 2001, numbers of US personnel there rose sharply, unreported to the UK Parliament. There are other US intelligence and early-warning bases around the country, which also primarily serve American interests rather than British.

Later this month, RAF Fylingdales will switch on its upgraded radar. Des Browne has announced that it "will contribute to the US ballistic missile system, alongside a global network of other US-owned sensors".

"The UK," he added, "will have full insight into the operation of the US missile defence system when missile engagements take place that are wholly or partly influenced by data from the radar at Fylingdales."

This amounts to a pledge of information post-event, but no part in any decision on how to respond or under what assumptions and instructions.

Parliamentary scrutiny is denied or obstructed in the name of national interest. It is inconceivable that if circumstances were reversed, the US Congress would tolerate such limitations on its powers. The British Parliament seems supine in comparison.

Those who defend against the infringement of British sovereignty should take note of this issue, rather than battering at the compromises British Ministers make in European negotiations. Labour and the Conservatives, in cosy consensus, justify the use of UK bases as extra-territorial enclaves that serve American ends.

The drive towards missile defence in Washington is driven by a mixture of industrial and military interests, and the identification of Iran as an existential enemy of the West. The British Parliament has the duty to question whether such motivations are compatible with British national interests.