The Prevention of Terrorism Act became law after a marathon session in the Commons.
The controversial Act enables the home secretary to impose "control orders" on suspected terrorists, requiring them to remain in their homes, wear tags and not communicate with other suspects.
The Bill provoked a number of rebellions among MPs and peers and the deadlock ended when the prime agreed to review the law in one year.
How should terrorism be tackled? Should the prevention of terrorism be higher on the electoral agenda? What do you think of the parties' policies on terror and security?
This debate is now closed for polling day. Thank you for your comments.
Hazel Blears from Labour, the Conservative's Andrew Mitchell, and Lord McNally for the Lib Dems answered your questions on anti-terrorism measures. Click on the link to watch the debate.
The following comments reflect the balance of opinion we have received so far:
Allowing detention without trial, such as house arrest, is wrong. Everyone has a right to clear their name in court, however heinous the crime they are accused of, and nothing can justify taking that right away. If these people are guilty and there is evidence, they will be found guilty, if not, then they shouldn't be locked up as if they are.
Emma, Peterborough, UK
Politicians are the biggest targets for any terrorist threat facing this country. If the population of the UK were asked would you like to spend £1bn of public money to protect them while they change laws dating back to 1215 I think the answer would be No!
Jonathan Ritson, Leeds, UK
I'm all for the anti-terror laws. They don't go far enough in my opinion. If you've nothing to hide you've nothing to worry about. Its all because of the do-gooding bleeding hearts allowing foreign terrorists in the form of 'asylum seekers' into the country.
K T Bell, Bradford, West Yorkshire
We should be dealing with the causes of terrorism, such as the gap between rich and poor nations, the Western oppression of the global markets and our subconscious racism, rather than converting democracies into effectively tyrannies. The anti-terror laws have given our government all the powers they need to start new terrorist groups here, and lead many dis-satisfied citizens into existing terrorist groups. We are playing into their hands. Why?
Chris, Romsey, UK
My history book says that within the Magna Carta (signed 790 years ago!), it states that all free men have a right to a free trial... and a council of 25 barons would imprison that anyone who tries to change it. Where are the barons and why is Tony Blair free?
Jonathan Ritson, Leeds, UK
There has to be protection against criminals, that is what the law is about, after all and I believe that prevention is better than cure. If we were to impose control orders to ensure public safety from terror suspects then that has to be right. Some people will complain but the main issue is to protect our country from the despicable sociopaths who plan to commit terror crimes. I think that if you are found in possession of bomb making equipment, guns or substances that are fatal to health then these people should accept what comes their way.
Britain faces ideological extremists ruthlessly dedicated to achieving acts of spectacular and lethal violence against those who either actively or merely passively, oppose their actions for political change in the world. If indeed you believe that the war in Iraq has further increased such risks, then some degree of encroachment on personal liberties must be responsibly demanded.
John Maclean, London
When the IRA was bombing mainland Britain, they were more of a threat to life and limb, and the economic interests. Yet the laws passed were proportionate, and politicians negotiated with the terrorists. The government is prepared to run a coach and horses through the centuries old laws that have been won by the sacrifice of many. This logic has only one answer. They represent the interests of the few at the expense of the many.
Mark Malik, Warsaw, Poland
Mark Malik, Warsaw: When the IRA was bombing mainland Britain we had detention without trial, the Guilford Four and the Birmingham Six miscarriages of justice. And we had the SAS carrying out virtual executions both in Ireland and abroad (like Gibraltar). If anything, I feel the response to Islamic terror is too modest and is hamstrung by liberal-fascism and the Human Rights Act.
With identity cards and imprisonment without trial and 24 hour CCTV, Blair is determined to turn this once great democracy into a European Zimbabwe style police state. We no longer have any freedoms or privacy. It's about time this country wakes up to what this government is doing in the name of protecting our freedom before it is too late, we may not get another chance.
I agree with most the anti-terror laws; however it should be High Judges, not politicians who should be allowed to use them to avoid misuse. Ironic how despite ridiculing the Thatcher administration for years, Tony Blair has become one of the most Draconian leaders since Oliver Cromwell.
Gil Eliav, Leeds
For me it's the key issue that prevents me even considering a vote for Labour. These laws undermine our legal, political and ethical systems. We now have all the instruments of a police state in place in the UK. I recognise the need to defend our society, but you don't do that by undermining its foundations.
Colin Wright, UK
The government has let in thousands of potential terrorists as asylum seekers who are wanted in their countries for various offences. We can't send them back because of human rights or they'd face death. Current terror laws can only be described closing the stable doors after the horse has bolted. You can bet your boots that these terror laws will cost a great deal, take a long time and achieve nothing! Typical Labour really, remember the hunting ban farce?
James, SE Cornwall, UK
"They that could give up essential liberty to gain a little temporary safety deserve neither liberty nor safety" - Benjamin Franklin. If we are prepared to jettison one of our most fundamental liberties so easily, God help us all if the terrorists actually attack Britain. Wake up people! We have a government prepared to use every trick at its disposal to legislate for imprisonment without trial and house arrest.
Mike Christie, Bacup, Lancs
All those that rebel about strong anti-terror laws will be the first to shout: "what is the Government doing?" if a serious terrorist attack was successful. If you have no guilty secrets why shouldn't you accept ID Cards, imprisonment without trial and all the rest of the measures being put in place? Stop complaining, the Government is only thinking of your safety.
John L Cooper, Great Yarmouth
If there is a threat so serious that we have to throw away the most basic human rights, how come the number of police hasn't been doubled? I cannot believe that whilst millions died for our freedom, we're so cowardly we give them up because we are "scared".
Jonathan Kelk, Dalry, Scotland
I would like some assurance that the Anti Terror legislation will not be used against those who wish to protest against government action, as is the citizen's democratic right. There is a distinct right wing trend here and in the US Patriot Act.
Elizabeth, Stockport, UK
Terrorism is a priority, but it needs to be dealt with sensitively and wisely. Firstly there should be less provocation - we should understand that a wise solution requires an understanding of causes. The Government should approach ethnic groups and work with them with respect of their culture and religion. The war in Iraq has increased the risk of terrorism, not lessened it. We should actively remind the world that we are a democratic country strong in human rights and not an imperialist empire. Now measures such as "control orders" appear to me to be desperate measures; I wonder how many terrorists may be lurking about unsuspected. What are we going to do about them?
Maria Daniel, Birmingham
Terrorism is real and we must be alert to defend the UK. However if such a defence is to rapidly remove the very fabric of our freedom and liberty then the terrorists are halfway to their targets. I urge readers to check up on the Patriot Act in the USA to see how citizens there in the "Land of the Free" have had their liberties damaged by such measures and what could happen here.
Jim Kirk, Basildon
The "presumed innocent" concept and segregation of power in democracy has been around since the start of democracy in ancient Greece. It has been a value that has survived for 2,500 years throughout a history of wars, barbaric raids, famines, drought and world wars. Now because Bush has started his "war on terror" they are trying to convince them that they are not that important. How can we claim to be fighting for democracy in the Middle East when we accept a "lesser" democracy at home?
Augerinos J, Greece
My only concern is now Tony Blair will scrap the democratic House of Lords because it has the affront to say no to him. I think this may be the start of the end of democracy in the UK. This must be taken into account at the next election, where the Labour party must not be given a third term as it could last 100 years after they change all the rules to allow them to stay in power.
Thomas D Jago, Khobar, Saudi Arabia
Charles Clarke argues that the House of Lords is being "unconstitutional" in its defiance over the Prevention of Terror Bill. On the contrary, it is being more constitutional than the Labour government are in the Commons because the Lords are taking time to consider this bill and thusly represent the people in Britain much more effectively.
Supporters of this piece of draconian legislation ought to ask themselves a simple question. What will be the government's response to a terrorist incident? The only response I can think of is to introduce even more draconian legislation. I can almost hear Charles Clarke speaking about 'measured and proportionate action' as he presents his bill for electronically tagging the population to Parliament.
Colin Simpson, Workington Cumbria
The terrorist threat does exist, but it was created by the actions and policies of current and previous Western (particularly UK and US) governments, who trained many of these terrorist groups. The threat is now greatly exaggerated to frighten the public into accepting draconian legislation and the loss of civil liberties.
Gareth Millsted, London, UK