At the time, London transport was pretty much at gridlock anyway and made the city pretty hard to live in IMO. It wouldn't have taken much to threaten the major

At the time, London transport was pretty much at gridlock anyway and made the city pretty hard to live in IMO. It wouldn't have taken much to threaten the major income-generating source of the country (look up the economics of the city of London). I don't even think it requires you to throw your life away. It could just be classified as civil disobedience. To be clear, I had no sympathy at all with the IRAs violent campaign. I'm just pointing out that committed civil disobedience could be pretty effective if you have people committed enough that they will already kill people and go to prison quite often (or blow themselves up for that matter).