The director-general of MI5 has given us a chilling assessment of the full extent of the Islamist terrorist threat. Last week she revealed that the security services are now monitoring 30 plots and at least 1,600 suspects. Many intend to cause mass casualties on the streets of Britain.

Eliza Manningham-Buller is a dedicated and highly professional public servant not given to flights of fancy. Her warning is one we must heed. We are now dealing with an enemy that has the will to massacre thousands of innocent people. Our task is to deny them the means to do so.

There is much common ground between the political parties and leaders on this. We need a strong and united response to terrorism. Supporting our security services and building community cohesion are aims best achieved by consensus, and I will always work with the government wherever possible, while pointing out where I think ministers are making mistakes.

Our government often confuses legislation for action. Ministers have been going in the wrong direction by simply passing more and more laws. We’ve seen an endless proliferation of new measures coming out of the Home Office, many of which end up never being used. I fear we’ll see more of the same in the coming Queen’s speech.

So what should be done? The home secretary is, in his own phrase, presiding over a department that is not fit for purpose. The immigration system is failing, prisons are chronically overcrowded and foreign criminals have been wrongly set free. Mr Reid has his hands full and cannot possibly take the lead in overseeing the fight against terrorism.

I am not advocating an entire new department of homeland security on the American model. That would cause far too much upheaval. Instead, what is needed is a Home Office minister for terrorism who is a full member of the cabinet, in the same way as the chief secretary to the Treasury is. Action against terrorism deserves a dedicated seat at the top table.

We need to change the way we patrol our borders. Despite repeated warnings this government has failed to understand how easy it is to get in and out of Britain undetected.

I was told by a senior policeman that the reason for government inertia on this vital matter is a logjam within Whitehall. Revenue & Customs fears that if the current system is overhauled, priority will be given to security rather than revenue raising. If this is the Treasury position, it is grossly irresponsible. The common sense solution, and one backed by an increasing number of people including the influential and yet Labour-dominated home affairs select committee, would be a dedicated border police force, to patrol every port and airport and exercise tight control over entry to, and exit from, Britain.

It is also time to change our priorities. Instead of imposing an ineffective identity card scheme on the entire population at an estimated cost of £20 billion, the government should concentrate resources on much more intensive surveillance of those who are most likely to do us harm. The security services are stretched to the limit. We should prioritise security, surveillance and Special Branch, not pieces of plastic. ID cards would not have stopped the 7/7 bombers.

I’m also convinced that we need to change our attitude to human rights. The Human Rights Act was a new Labour flagship but its totemic status has made ministers unwilling to acknowledge how much it is hampering the fight against terrorism.

It is almost impossible to deport even the most ruthless foreign terror suspect from Britain. The European convention on human rights, upon which the Human Rights Act is based, has been extended by case law far beyond the original intentions of its founders. It is time to replace the Human Rights Act with a British bill of rights that will enable ministers to act within the law to protect our society.

If MI5 tells the government that a foreign national is a dedicated terrorist and a danger to national security, then the home secretary should be free to balance the rights of the suspect with the rights of society as a whole and proceed with deportation if necessary.

There is one law that does need changing urgently. Telephone intercept evidence should be made available to the courts. The police have been calling for this measure for some time. It must be intensely frustrating to listen to tapes of terrorists plotting massacres yet be unable to lock them up because such evidence is inadmissible.

The final change needed is a much more rigorous approach to combating Islamic fundamentalism. The government seems confused as to what fundamentalism actually is. On the one hand ministers — perfectly reasonably — express concern about women who wear the veil while teaching. On the other hand they pay for extremist preachers of hate such as Sheikh Yusuf al-Qaradawi, who supports suicide bombings, to attend conferences.

We need to embrace genuinely moderate Muslims, the majority who love Britain and want to live in peace, while confronting the fundamentalists. Those who distance themselves from terrorism while seeking to radicalise young Muslims into despising the West are part of the problem. Groups like Hizb ut-Tahrir should be banned.

The response to terrorism goes beyond legislation, a point which the government does not seem fully to grasp. We must make the necessary changes, stand together and keep our nerve. Then we can and will defeat the terrorists.