The invasion of Iraq in 2003 by the US and UK, showed the world that nuclear weapons were not being developed in that country and furthermore, post the invasion, that they could not be developed there. Without that assurance, I believe that the west's negotiators, even with the influence of economic sanctions, backed by cyber attacks, would have had little chance in delaying Iran's nuclear program. If Iran had continued to develop nuclear weapons, it is likely that Saudi Arabia would have followed a parallel course. A senior person within the Saudi government is quoted as saying that they would "not wait one month" if Iran acquired a nuclear bomb and allegedly, Saudi Arabia has an agreement with Pakistan for the provision of nuclear warheads, should they be required. We could by now have been seeing a nuclear stand-off between the militant Shia Mullahs on one side of the Persian Gulf and the hard line Wahhabi Sunnis on the other; both of which hate an equally nuclear armed but much beleaguered Israel! By taking Iraq out of the equation, the US and UK have made it possible to stall a nuclear arms race in the Persian Gulf; an area that fuels the global economy.
Possibly the disbandment of the Iraqi army (against the advice of several military heads) was a major mistake. It is also likely that had far more resource and persistence been applied by the invading powers, stability could have been imposed long enough for proper institutions to develop, which might have stabilised the country. The invasion itself however has paved the way for negotiators to resist, for the time being, a nuclear crisis between two regional powers that are presently funding Shia/Sunni proxy wars throughout the Middle East. Local turmoil may be the result and some of that will affect us in the UK but globally I believe we are safer as a result of the 2003 invasion of Iraq and if for that reason alone we should not be apologising.
The 2005 London bombings that killed 52 people and the recent Paris attacks that killed 130 are an obvious sign of the affect that Middle East instability is having on our society. The flood of refugees from the stricken areas is another. Dramatic and horrific as those events may be the real danger to us generally is that we over react, allow them to disrupt our way of life and give the impression that we are running scared. The closing down of Brussels for several days, Capital of the European Union, must be regarded as a propaganda victory for ISIS! Guarding against further attack is of course a task that must be afforded the utmost resource but we must also apply a certain amount of proportionality. In 2013 in the US for instance, there were 33,169 firearm related deaths. Many of those also left a trail of bereaving relatives and friends. The UK is no stranger to terrorist acts. In 1605 for instance, Mr.Guy Fawkes and accomplices attempted to blow up the houses of parliament. They were foiled in a success for the security services of the time. Since then there have been many assassination attempts and terrorist attacks, some of them successful but we are still here.
If the prima-facia reason for invading Iraq was to stop regional nuclear weapon development and proliferation (there are also other reasons), one has to ask the question, 'whose nuclear weapon development'? Could it be that the Blair/Bush combination had a chess player among their advisors, who, when viewing the greater picture, saw that the sacrifice of a pawn (Iraq) in 2003, might be of benefit several moves into the global security game?