There aren't any British soldiers, so far as I am aware "fighting and dying" in any of the so-called Arab Spring countries.
Personally I think it is incredibly unlikely that any of the N. African countries will sucumb to extremism. The dictators in those countries, for many years played on Western paranoia about "Islamic extremism" to maintain their hold on power, repressing as they did so, political oppnents, a handful of whom, for all we know might have gone on to be dangerous extremists but who knows? Gaddafi himself conducted a terrorist campaign of his own against the west, including Britain, involving the small matter of downing a civil airliner, having a policewoman shot, and funding IRA and Loyalist terrorism in N. Ireland. On the other hand Ben Ali in Tunisia was as nice as pie to his western allies, while behaving differently at home, So, vast differences there, even between two neighbouring countries.
Also, the average Tunisian, Libyan and Egyptian didn't risk life and limb to oust their rulers just to kowtow to a different one. If they rejected secular repression, why would they accept religious fundamentalism?