Could the US have convicted Osama Bin Laden for 9/11?

I'm in the small minority of liberals who are bothered by the possibility that the soldiers who were sent after Osama Bin Laden were given explicit or implicit orders to kill him, or at least the understanding that his death was preferable to capturing him. 

I really would have preferred to see him on trial.  Partly because it better upholds the Western ideal of justice, and partly because I think it would be a more effective victory against Al Qaeda. 

So I wonder if once they knew where he was, and realized that getting forces to him was not going to be terribly difficult (not without risk, but a peaceful suburb of Islamabad sounds a lot easier than the remote tribal mountains we kept hearing he was likely hiding in all these years), they must have considered what to do with him if they captured him. Trying him for planning 9/11 certainly seems like it would have been the first thing considered, and the question must have been asked "what evidence do we have that we could present in court that could actually be used to convict him?"

I suspect we (meaning US authorities) know Osama planned 9/11 through a variety of hearsay and indirect ways, but not ways that would survive an actual civilian Article III court, or maybe even a proper Military Court-Martial.  I doubt the US has much primary evidence in the form of personal eye-witnesses or original documentary evidence.  It's likely not much of that actually ever existed.  If Bin Laden really is the conceptual thinker and philosopher-king of Al Qaeda, he may actually have not had much real involvement in the plan. Regular mafia bosses regularly make it difficult to stick any particular charge to them by staying above the operations, if no one "rolls" on Osama to testify that he personally ordered or authorized the 9/11 operation, a Judge might just toss out the charges.

Then of course some or all of the evidence they do have is probably classified and disclosing it would necessitate disclosure of other secrets, expose agents etc.  

I'm sure they would have next considered using one of the Gitmo kangaroo courts which accept secret and hearsay evidence, but no way a trial of this level of publicity could be conducted under those rules.  This would have worldwide attention, and a rigged trial would be particularly counterproductive to the goal of demoralizing Al Qaeda and persuading politically radical Muslims to stay peaceful. 

I fear this, more than anything else may have driven a decision to let the special forces kill him while giving the White House some level of plausible deniability that they had ordered them to do so.  I even wonder if America could have convicted Bin Laden for the Cole bombing, or the African embassy bombings.  Even if they could, this would have been a big let down, putting Capone on trial for tax evasion.

None of this is to go down the Truther road.  I don't have any reason to doubt Osama did lead the plot to do 9/11, bomb the Cole or the rest, just that I can well believe that no one was too sure they could actually get a Judge and Jury to convict him of these things, most especially 9/11.

If so, killing him certainly solves this problem in a most convenient sort of way, but as the initial stories of Bin Laden fighting back and hiding behind a human shield have begun to unravel, the suspicion that he was essentially assassinated becomes more problematic.  Certainly it won't hurt Obama in domestic US politics, but history at least will remember.  If the Israelis could try Eichmann, I'd like to think America could find the courage to try Osama, so I really do hope the instructions were to capture if possible, and his shooting done out of some perceived operational necessity.