Gordon Brown’s speech last Thursday at Westminster University was striking for a lot of reasons. It has been a while since a Labour prime minister spoke so forcefully about a thing called freedom. Whether out of an attempt to regain the political initiative or because he has seen abuse of executive power up close, Brown homed in on one of the more worrying threats to liberty today: overweening executive power. Blair revelled in this power, as George Bush and Dick Cheney do on a far larger scale.

In Britain, most of the leading parties support greater parliamentary control over war powers, especially after the debacle of Iraq, a war whose mistakes were compounded by too tight a circle of executive decision-making. In America, congressional resistance to presidential power is nearing a historic nadir; and we live in a time of a resurgent imperial presidency. The attacks of 9/11 would doubtless have increased presidential power. Emergencies always do. But no one could have predicted the sheer scale of what has happened and the extreme to which it has now gone.

There is one core reason for this and his name is Dick Cheney. Many of us who were initially sympathetic to the Bush administration and sup-portive of the wars in Afghanistan and Iraq have spent the past six years trying to make sense of what appeared to be a series of inexplicable mistakes: the secret authorisation of torture against US law and the Geneva conventions; the use of false intelligence in waging war on Iraq; the construction of Guantanamo Bay and the imprisonment and torture of countless innocent people across the globe, some in secret black sites; and the repeated, express intent of the president to ignore laws passed that he had signed – because they allegedly violated his constitutional authority as president.

In the space of six years it is no exaggeration to say that the imperial presidency launched by Harry Truman and epitomised by Richard Nixon has never been this strong or this enduring.

How did this happen? It is the usual mix of unpredictable events and peculiar human beings. Cheney came of age as President Gerald Ford’s chief of staff, in the wake of Watergate. As proof of Nixon’s criminal violations of the constitution emerged in the Watergate hearings, Congress passed many laws to restrict presidential overreach. From the War Powers Act to laws preventing domestic wire-tap-ping without a court warrant, it was Cheney’s first president who bore the brunt of the Nixon backlash.

In the long arc of American history it was a return to the intent of the founders. In America’s constitutional system preeminence was originally given to Congress, but the president was given the power to act as an individual without congressional deliberation when events, especially to do with national security, required swift and immediate action.

Lincoln exercised such emergency powers at the beginning of the civil war, but soon went to Congress to authorise his actions retroactively and place them under the rule of law. The constitution clearly gives Congress both the right to fund or withhold funds from the executive but also to legislate the rules and laws by which the executive operates.

Cheney never believed this and the Ford experience seared it more firmly. He had long held a theory of executive power that a tiny minority of scholars give credence to: that the president alone has the right to declare war and in wartime has the right to determine everything that could possibly pertain to that war.

In 1990 Cheney opposed the first President Bush’s decision to ask Congress’s authorisation to enlist half a million men to repel Saddam Hussein from Kuwait. Although he never made a serious issue of it in the 2000 campaign, he did, when asked, repeat his view of presidential power. In the years after Watergate, moreover, a small band of far-right scholars also developed this unitary executive theory and worked hard to insinuate it into mainstream scholarship and constitutional interpretation.

When Cheney became vice-president, to whom did he turn to staff the critical legal positions within the administration? Those same legal scholars. In most circumstances this might have led to minor domestic scraps. But when 9/11 came the consequences were momentous.

The use of “severe mental or physical pain or suffering” to acquire intelligence is plainly illegal under US law, the Geneva conventions and the United Nations treaty. Under traditional constitutional theory, those are laws that the president is bound by oath to enforce. But Cheney’s circle argued, against all American history, that the law did not apply to the president in wartime. He could do whatever he liked and the sole role of Congress and the courts was to fund and rubber-stamp it.

They argued this, moreover, not just in an emergency but permanently because this war, against an inchoate enemy who definitionally could never surrender, was unending. This applied not just abroad or even on the battlefield but everywhere, because the fight in this war included the homeland. So Cheney’s legal circle simply insisted that the law did not apply to them any more. Habeas corpus did not apply. Getting court warrants for wire-taps did not apply. Restrictions on going to war did not apply. And there was nothing anyone could do about it.

When Congress responded to Abu Ghraib and the revelations of torture across every theatre of war by banning torture by statute, the president signed the law – and then appended a signing statement that he would abide by it only if it did not impede on his own view of his constitutional powers. And he believed it did.

Little of this was aggressively or explicitly or publicly asserted by Bush or Cheney. That is not Cheney’s style. But you could infer it from slips of the tongue by his pupil, Bush. The president has referred to his role as “the decider”, which is not exactly “the presider” and “executor of the laws” passed by Congress that the founders had in mind. He also declared that he has had one “accountability moment” in office – the 2004 election. After that the American people simply had to watch or obey. Hence his sole advice to Americans after 9/11: go shopping. This was not their war. It was his and he would wage it as he wished.

What it amounted to, in fact, was a neo-monarchical concentration of power in the hands of one man who came to exercise power on an unimaginable scale – the power to take the most powerful country in the world to war against any country or person anywhere, the power to seize and hold indefinitely any individual deemed to be an “enemy combatant” and the power to torture – the most dangerous of all powers ever held by executives in western history.

By refusing to involve the American people fully, either by a draft or even by taxation, the president was telling the world that he needed no one’s permission and no one’s support to do what he wanted with the volunteer army and weaponry at his command. The cost thus far has been more than $2 trillion of other people’s money.

Now remember: the decider keeps warning Iran that it cannot have a nuclear weapon. The vice-president a week ago warned of “serious consequences” if Iran passed a certain threshold, the precise phrase he used to warn Iraq before the last war. The president last week defined that threshold of war not as Iran’s acquiring the full materials and equipment for a nuclear bomb but merely possessing “the knowledge” to make it.

Remember this: the decider believes he has no need to consult Congress or the American people in going to war against Iran if he thinks it’s necessary. Suddenly Brown, for all his faults, seems a comforting figure. At least he is answerable to someone.

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