Yes they did have justification! Didn't you read what I said? They were harboring(giving refuge) to a person we wanted to bring to justice or kill. I never said anything about the Taliban threatening us, they we're AIDING and EMBEDDING our enemy.
Of course not! We're the good guys! Why would we meet the demands of terrorists? Terrorist that brutalize its own people?
According to international law the US had to request the Afghanistan government hand over people alleged to have committed crimes. But there is no legal basis for starting a war if that country refuses to hand over criminals. You would have a hard time finding any international law supporting your belief.
But lets assume you are correct. If the US can do this, then so can any country.
According to China, Canada is harboring a number of people accused of corruption by China. Applying the same principle, China would have the same right as the US to invade and occupy any country which refuses to hand over people they believe are criminals. Does that mean you support China invading and occupying Canada because they believe Canada is harboring criminals?
Oh excuse me, that's right, the principle of invading and occupying countries is only afforded to the good guys. China isn't a good guy so they don't have the same right to invade and occupy other nations as the US which is a good guy, even though their justifications for invading and occupying Iraq turned out to be completely bogus.
Another fundamental principle behind your logic is that good guys are always right and anyone who disagrees with good guys are are the bad guys and they are always wrong.
So how do you determine who is a good guy and who is a bad guy. Is it by hat color?
Good guys can detain people indefinitely without trial and torture them because of their goodness. Bad guys can't commit heinous acts like this as that would only confirm their badness. When the US tortures people or invades countries without provocation, it indicates their goodness. When other countries do exactly the same thing they are evil, unless they are the good guys, then its OK.