Most of us would see this as an absurd question. The answer is clearly no. Not only is it unjust, but it is immoral, and illegal, and incompetently waged to boot.
However, an esteemed colleague of ours will be trying to argue otherwise this Saturday, as he shares with us his master's thesis. I applaud him for undertaking such a challenging effort and I greatly look forward to hearing it.
Nevertheless, as someone who devotes much time to researching current political events (perhaps moreso than any of my fellow students), I've taken it upon myself to refute him to the best of my ability in the following question and answer session. I'm not sure what argument(s) he will make, but I shall come prepared.
Toward that end, my good friend who goes by the handle "Crypthanatopsis" has undertaken a request of mine to compile some research and present a multi-installment essay on his blog, Prestimentitation, thoroughly refuting the justness of the Iraq War.
He's doing me a great favor here since other duties prevent me from devoting as much time researching this as I'd prefer, and his work is quite good. He's not an academic, but he has more than the requisite level of talent necessary for sound scholarship.
So do check it out.