I'd first like to say that, on balance, I agree with the opinions above and believe liberties are being sacrificed for "security".
However, perhaps you should look at things from another point of view for a moment, mainly because a discussion where everyone agreed would be fairly dull. The Government's main priority (aside from re-election, obviously
) is the safety of it's citizens and preserving the sovereignty of it's country. Whether they like it or not many western governments, in particular the US and UK, are fighting a "War on Terror" that threatens to destroy both of these principles. The issue is that is a war , but it's a war against an unknown, disassociated enemy who can't be fought using the conventional means adopted by countries since wars began.
The only members of this enemy force within the government's reach are the people who actually carry out the atrocities. These are often poorly-educated young men indoctrinated into thinking they are fighting for Islam. Islam, which shares a common root in Arabic with the word "salaam", meaning "peace". Catching these people is not going to harm their cause in the slightest, if anything it will make it stronger.
I think Taw (perhaps unwittingly) hit the nail on the head when he said that "the majority of the population were in favour of this post 9/11". Public opinion is an extremely fickle and short-term thing. Post 9/11 people were calling for retaliation, the government's opinion polls rose exponentially and the American army rode into Afghanistan on a wave of public support. Now, five years later, the event is sufficiently distant that people are able to get on their high horse and condemn the government for trading their civil liberties for security. If terrorists had succeeded in carrying out their attack in the UK last thursday - potentially the largest ever terrorist attack - then I'd imagine public opinion would swing the other way and the government would once again be the protectors of the free world. As it is, despite foiling the plot and saving hundreds if not thousands of lives the goverment is now being condemed by the public and media for the disruption they are causing. Airlines like Ryanair and Virgin are now complaining about their falling profits and demanding compensation from the government, but London Heathrow is the busiest airport in the world and as such the security needs to be rock-solid. When some airlines essentially demanded the security measures be stepped down or they would take legal action against the government I think John Reid (the Home Secretary) took a very commendable stand and near enough told them to take a hike.
Whatever the government does will be criticised, whether for genuine reasons, by politicans looking to further an agenda or by people who disagree simply because it is the government, and in some way they're doing their bit to "fight the machine".
The governments of the western world are fighting what is likely the hardest war they have ever fought, and to be brutally honest I'm not sure it is one they can win. Perhaps all that remains to see is whether they are brought down by the terrorists or by their own citizens...