However, Trim Stab old fruit, surely the point is that while these new concerns are demanding of attention enough. The truth is they are additional concerns to address, not replacement ones?
Yes, but we have to make a choice of where to spend limited resources.
The only deadly attacks on UK soil since WW2 have come from terrorists, and that is likely to remain the case for the foreseable future. MI5 are the lead defence agency for that threat. They have an budget of approx £400m. They have gone on record that part of the reason the 7/7 bombers slipped through the net is because they did not have enough resources to follow up every single lead.
We could double or triple the annual budget of MI5 by cutting (if it were possible) only a small fraction of our air defence budget.
We have to prioritise spending on the real threats that face us in the future, not on historic threats no matter how much "nostalgia" we may have for them.