The fact the USA were forced into the war by the devastating attack at Pearl Harbour in December 1941, an attack on their own homeland, showed that every country is a potential target for attack.
After the 11th September, the world was again changed. It became clear that enemies had the knowledge and the ability to strike deep into the heart of a country without warning. The terrorists responsible for the atrocity came from the Middle East, some from Saudi Arabia and others from the countries around Afghanistan, countries previously considered by the West to be so far off that they were not a immediate danger or threat.
"Far-off" is not applicable in the world of today, as everyone is in range of someone else. If indeed Iraq had the weapons of mass destruction that George Bush and Tony Blair claim he did, then other countries would have no choice but to get involved for another main reason. Oil.
Iraq is a member of the oil cartel OPEC, and has the second largest oil reserves in the world, second only to Saudi Arabia. The world's complete dependence on oil partially explains why the West was so worried at the prospect of Saddam Hussein having the weapons of mass destruction. If he did possess weapons of mass destruction, then he could single-handedly start a war involving the entire Middle East. Oil prices would consequentially rise uncontrollably, and the world would grind to a literal halt, sending many economies straight into a recession.
As a result the West, with countries such as Britain and the USA so dependent on oil, must ensure that Iraq doesn't harness the potential to cause such a crippling conflict. However morally wrong this maybe, the fact remains that Iraq possessing weapons of mass destruction was a risk Mr Bush and Mr Blair were not willing to take.
The advances in technology in the 20th century have meant that the average citizen now has access to the lives of people all over the world.