The citizens of London *did* put up with a much deadlier threat throughout the IRA's 1980s era bombing campaign, and while *reasonable* security measures (like the Ring of Steel around the City of London) were taken, the UK did *not* suspend civil liberties, did *not* start indiscriminately leveling Ulster or Liverpool, nor did the UK invade and reoccupy Eire. The most common reaction was to shrug it off and say "[we've] been blown up by a better class of bastard than this". And in case we've forgotten, that campaign included hundreds of millions in property damage, including the gutting of Center City Manchester and the destruction of the national-rchitectural-treasure Baltic Exchange, and damn near killed Margaret Thatcher's entire Cabinet. A Qassam would have to get a very lucky hit in order to render a wood-frame house structurally unsound.