I don't understand why you think I "forget" anything or that my example is "imaginary". I am proposing a response and using a well known phrase to illustrate it.
I disagree that 'it's going to happen whether or not we want it.' In the abstract yes, but again you're back to saying counterterrorism is pointless. I also disagree that 99.9 of the damage is self-inflicted although a high percentage is. US reaction to terrorism is actually mild by comparison to most countries. The UK is festooned with video cameras and terrorist suspects are subject to different detention conditions from regular criminals. In Spain you can expect to undergo security checks when taking a train. Perhaps you could furnish some examples of countries that have a more laissez-faire approach to terrorism for comparison.
As for 'keep calm and carry on' I urge you to look into the historical provenance of the phrase. For one thing it was dreamt up as a campaign to reassure a population facing total war, and for another it was shelved at the time (despite some 2 million posters have been printed) because officials realized it was patronizing and unresponsive to public concerns.
Terrorists are in short supply, while methods of attack are essentially unlimited. Effective counterterrorism will attack what's in short supply. In other words, it needs to look for terrorists, not attempt to stop every single conceivable method of attack. The former can be useful, the latter is fruitless.
How many countries have carried out something as catastrophically stupid as the 2003 invasion of Iraq in response to a terrorist attack? If you want a country that took a milder approach to terrorism, given that, I'd say "all of them". Yeah, we didn't completely trample over everybody's civil liberties, we just killed a ton of people, put the government in deep debt, and wrecked the economy.
Also, did you really use "terrorist suspects are subject to different detention conditions from regular criminals" as an example of how the UK reacted worse than the US? Have you not heard of Guantanamo Bay? How many people did the UK hold indefinitely without trial because they were too dangerous to be released but could not be convicted of a crime? (To be clear, this isn't completely rhetorical. I wouldn't be surprised if the answer is not zero. But I also don't think it's in the hundreds.)
I don't know why you persist in thinking that I'm somehow unaware of the origins of "keep calm and carry on". Again, I'm merely using it to illustrate an approach, not saying we should replicate the conditions under which that phrase was conceived.
As you are surely aware, we don't have a reliable method for distinguishing terrorists from everyone else, notwithstanding the best efforts of intelligence agencies engaged in various sorts of spying. Targeting particular attack vectors is of course less than ideal, but if one receives a credible tip along the lines of 'agent X will attempt to transport a 'battery bomb' onto a US bound flight this month' then you can't blame security services for trying to leverage that information. There may even be a second-order purpose for announcing it publicly, eg to instill paranoia among potential terrorists about the leakiness of their OpSec or suchlike. So no, I don't think that such specific directives are necessarily pointless.
How many countries have carried out something as catastrophically stupid as the 2003 invasion of Iraq in response to a terrorist attack? If you want a country that took a milder approach to terrorism, given that, I'd say "all of them".
I might point out that the UK, and a lot of other countries joined in the invasion of Iraq. As for Guantanamo bay, I don't think that's an appropriate comparison. Most people held there were either captured in Afghanistan and a few kidnapped and subjected to 'extraordinary rendition', of them in the context of a hot war. I'm talking about people arrested on suspicion of terrorism, ie neither the Tsarnev guy in Boston nor any of the various would-be terrorists nabbed by the FBI over recent years have been sent to Guantanamo (despite calls for that some ultraconservatives). In terms of judicial process, they're subject to the same regime as any other person detained on suspicion of criminal activity.
In fact, the UK government did imprison a group of men indefinitely and without charge post 9-11 (although the law in question was overturned a few years later because it was in conflict with EU human rights law): http://www.liberty-human-rights.org.uk/human-rights/counteri... Britain is about make some legal history with its first secret trial (http://www.thestar.com/news/world/2014/06/12/core_of_uk_terr...). Looking farther back, for several decades Britain dealt with its terrorism problem in Northern Ireland by removing the right to a jury trial for many offenses (http://en.wikipedia.org/wiki/Diplock_courts) and for a number of years by internment (http://en.wikipedia.org/wiki/Operation_Demetrius - note that almost 2000 people were held prisoner without trial, quite a few more than Guantanamo Bay ever held).
Now, I wouldn't expect you to know all this - I grew up over there so it's easy for me to cite examples. But instead of rudely asking me if I've ever heard of Guantanamo Bay, perhaps you might acknowledge the possibility that I know what I'm talking about. I could dredge up a variety of examples from other countries in various stages of socioeconomic development, but since the UK shares a language and a common legal heritage with the US it seemed like the most obvious point of comparison. I stand by my argument that the US response to terrorism, while of questionable effectiveness, is not nearly as unusual as you seem to think. Indeed, in comparison with prior actions of the US it's fairly mild, sad to say; consider the Japanese internment of WW2, or historical punitive campaigns that would be regarded as genocidal war crimes today, such as the Phillipine-American war of 1899-1902, or for that matter the Vietnam war. Historical awfulness is no justification for bad governance today, but nor are today's problems as bad as you suggest.
