N.I. was as bad: you must have a short memory (or not been alive) if you can't recall it.
In some senses it was worse because it occurred within such a small area, those living there weren't just scare of 'it might happen', they know it would. The it might happen occurred in English cities certainly, but no in Northern Ireland. Imagine that, day it, day out. I think I read that every (extended) family in Northen Ireland has a member killed because of 'the troubles'.
It was certainly different, today's terror attacks are about religion (religion was involved in N.I. but it wasn't the reason), they seem to occur anywhere, without warning, and involve someone who doesn't seem afraid of dying, nor killing those who are in the same religion that they think the are doing it in the name of.
You still can't let it stop you, though it'd be wise to think about where you're going on holiday it you are still inclined to want to. Yes, Birmingham, Leeds, Glasgow or Cardiff could be targeted as well as London, but there's high security alert in place on a lot of cities without you being aware.