The death of Osama Bin Laden is a reason for both rejoicing and sorrow.
The end of the leader of one of the most militant extremist groups going around, has to be a reason to be pleased. Extremism of any flavour is abhorrent but when it is used to justify wholesale butchering, it ascends to a whole new level.
The death of anyone in stupid, pointless conflict is also a cause for sorrow. However there is a distinct possibility that Bin Laden's passing shall be seen as creation of a martyr thereby birthing yet more violence, more reprisals and so the cycle would continue.
Far more intelligent people than I have been unable to come up with a resolution of the issues behind the rise of militant extremism so I shall not attempt to do so here. However blatant manufacturing of excuses to go to war as exemplified by the Bush Junior administration, supported by Britain's Tony Blair and Australia's John Howard, not only fail to address those concerns, they created far more. Let's be honest - we were presented with a complete load of bullshit to justify that Coalition of the Willing or whatever the heck it was called. The phrase Weapons of Mass Destruction eventually became nothing but a bad joke because of the way it was used in the Iraqi context.
There are times when I briefly consider worrying about environmental issues is a waste of time as we will have already killed ourselves off as a species before environmental problems could do so.