That is the only thing that matters. However long it takes to approve and implement your "few simple procedures" is time when intelligence integrity is compromised.
Yes, because everyone knows that the US's intelligence services are totally unable to function without their morning coffee and the ability to read the last diplomatic gossip columns from the DoS.
Manning does not get to take credit for the unforeseen consequences of his actions. He published every single classified file he could get his hands on.
No, he leaked them, he didn't publish them, the media did that, and we don't know that he took everything "he could get his hands on" at all. From my understanding having read up on it all, he took what he considered to be in the public interest to know.
if we're to assume that the "none of the information is important" isn't simply downplay (along the "it's not such a big deal that the missile test failed" line, which is more likely exactly what it is; the US can't very well publicly state that the secrets of the American military universe can, in fact, be gleaned from the data), then it's purely chance that none of the files Manning distributed were so crucial.
The assumptions are based on military commentators, not the military trying damage control.
Nevertheless, he stole all the classified data he could and gave it to somebody with the understanding that it would be published globally
And that is what he should be charged with, but that isn't treason.
where the US's military enemies could freely access it.
Free access doesn't equate to aid and comfort.
ETA: Put another way, imagine a Civil War era soldier who is tasked with delivering a message to the front lines saying "reinforcements will be at this location", and instead of delivering the message to the intended recipient, he takes it to the enemy commander. If, while that message is being delivered, the original commander changes his mind and decides to send the reinforcements to a different location, our soldier doesn't get out of a treason charge simply because the instructions he gave to the enemy ultimately proved invalid. The fact of the matter is, he was given material which at the time he either knew for certain, or had reason to believe, was crucial to the battle plan and he chose to give that material to the enemy; end of story.
And for doing that he'd deserve to get a treason charge too. However, unfortunately for you, your nice little story isn't anything like what Manning actually did with these leaks.
Manning wasn't tasked to deliever a vital battle instructions or troop locations. Nor did he take any information directly to any enemy commander. Finally, the value of the information didn't change between his getting it and his handing it over.
A closer analogy would be this:
Our solider is tasked to read all of the Commander's diaries on a daily basis, then condense the information in them into a report and pass that on to the General. In the course of his duties he starts to read things he feels are wrong, some reports about soliders looting farms, shooting civilians, and also a few rather uncensored descriptions of local milita commanders and the general staff. He copies down these reports and sneaks them out to a national newspaper reporter who then prints them.
Has this soldier commited treason? He has certainly embrassed his commanding officers. He has let out information that they didn't want released, he may have even allowed that information to get into the enemies hands, though it's not likely that much use to the them, if any use at all. But in all of that there is zero evidence that he has provided any aid or comfort to the enemy. He still should be charged for the breach of confidence, but that's it.
