The Republic could whomp up a military quickly once hostilities broke out. Societies under attack have to do that, or they won't survive. The question is, were the clonetroopers vital to the war effort or could the Republic have gotten by without them? If the former, then the Republic isn't worth saving.
If the clonetroopers were needed as an emergency stopgap measure to stave off immanent defeat, then fine. But steps should be underway to cease production and transfer the war effort over to "normal" Republic citizens. Producing clonetroopers is morally reprehensible and even under an emergency situation, it's questionable. Is it okay for a society to do anything in order to survive, no matter how bad?
So the Jedi did nobody any favors by allowing the clones to avoid forcing the Republic to answer a very fundamental question - which the Jedi should understand is fundamental. So maybe their fatal flaw is in avoiding a possibly painful truth.
Why do the jedi serve a corrupt oligarchy in the first place?
How corrupt is it? Is it salvageable? All systems of government have their problems, just look at Congress for proof.

But the question we need answered, is whether the Jedi are simply being fools in thinking the Republic is worth saving. Whether or not Republic worlds could raise a military capable of defending the Republic if they had to, is one important factor in assessing whether the Jedi are fools.
A clever way to handle this storyline is to keep it ambiguous, so that Obi-Wan and Padme might consider the Republic worth defending, and Anakin might decide the opposite, and there's no clear way of saying who's right or wrong.
And to do that, it would help to establish that the clonetroopers were a stopgap emergency measure, and that the war wasn't expected to take as long as it has, and now some elements in the Republic are getting concerned about the morality of continuing this immoral practice, while others are worried that transitioning away from an efficient and experienced clonetrooper military will allow the Separatists to gain too much advantage, and others are just corrupt and want the clones to keep doing their dirty work but are hiding their true attitudes behind a pragmatic argument. Then you have a messy situation in which reasonable people could come to very different conclusions.