This is an excerpt from a recent editorial in The Financial Times:

Financial Times, London, on President Bush and wiretapping:

President George W. Bush's admission that he ordered a secret wiretapping programme monitoring international calls by US citizen's suspected of links to al-Qaeda, bypassing the system of judicial supervision established by law, has ignited a firestorm in the US and threatens the renewal of important sections of the Patriot Act. Rightly so.

This is not a question of what powers US law enforcement and intelligence agencies may need to combat the threat from terrorism. It is a question of who should authorise any necessary curtailment of liberties established in the constitution and elaborated by legislation and precedent.

In declining to seek authority to do so from Congress, and ignoring the courts, the White House has made an extraordinary claim of executive prerogative. It appears to assert the unilateral right to alter the legislated balance between civil liberty and national security for the duration of a war on terror that could last for generations. If sustained, this would fundamentally alter the common understanding of the nature of the separation of powers in the US political system.

The US has a system for authorising wiretapping, created by the Foreign Intelligence Surveillance Act of 1978 and modified by subsequent legislation. Normally, officials seek a warrant from a special court. However, in an emergency, the president is empowered to order wiretaps on his own authority, provided officials go to the court for retrospective sanction within 72 hours. This process does not appear onerous: requests for wiretaps are hardly ever refused. It ought not to cause delays and it should not jeopardise investigations, since the court meets in secret.

Still, it is perfectly possible that the process needs amending in some way. Many such changes have been made by Congress since September 11, 2001. The crux of the matter is that the White House here saw fit to proceed without Congressional authorisation and with only the most limited consultation.

This is not the first administration to assert sweeping commander-in-chief powers in time of war. But the claim cannot be allowed to stand, not least because this is a war, if it is one at all, of indefinite duration.

The executive does need greater latitude in an age of terror. But it can only demand this on the basis that it will seek legislative authority for extra powers and will not abuse them. The problem with renewing the Patriot Act is that the administration has not vindicated the trust legislators placed in it. Mr. Bush can hardly demand expansion of state powers as necessary in the war on terror, while reserving the right to operate beyond them.

The Founding Fathers made Congress, not the Presidency, the first branch of government. It must reassert its sole right to frame the rules that govern the relationship between government and citizen or risk sliding into constitutional irrelevance.