I'm beginning to wonder just how many people here know what free will is. We need a definition before anyone discusses this issue again. Either we are robots or we have free will. That our will is influenced and controlled and manipulated by our own nature and by outside forces make no difference. God gave Adam free will. God is not responsible for our choices. If He were, He would be complicit in our sin.
So define it. Your statement that we are either robots or have free will still leaves a huge range of definitions. I can say that even robots have real choice, since that is my usual definition of free will, but I don't mean we are therefore robots.
I have come to group people who argue this subject into two kinds of mind. There are those who can't see two individuals being responsible, as though the thief (for eg) had not been raised by thieves, so that if it can be said that he was raised by thieves, those who raised him are the ones to blame, and he is not. Then there are those, who, like me blame the thief for his own thievery, and recommend justice according to his crime, but admit to his upbringing having something to do with it. If they were wrong in bringing him up that way, then
that is their crime --not the actual theft, though the individual theft does imply a defining degree to their crime. Nevertheless, while I admit to some guilt on their part, in the thief having committed the thievery, I notice further that those of the first sort, who blame the one or the other-- not both --see little difference between the rights and justice of a human that causes vs the Creator that causes. Such people invariably see God as being subject to "what is", as though there is justice and laws of physics and laws of logic quite separately from God. They make God subordinate to "what is".
I find a huge difference in the blameability of the Creator vs the Created. You say if God is "responsible" for our choices, he would be complicit in our sin. Do you deny he has absolute control? If he does not, does that imply some principle of randomness or chance? Are they supreme over his control, in your wish to justify his causing of effects? Do you go so far as to find it necessary to say such things as "Well, he gave up that bit of control." in order to say he is still sovereign?
Again --if there is nobody (but chance, we might be tempted to say) to blame for the sinner's own sin but the sinner, even though there are myriad causes, such as genetic disposition, environment and other circumstances and so on, why should the fact that the Creator caused those circumstances make the sinner any less to blame?
Meanwhile, admitting that the intention of the One who sets up those circumstances is for good, in the end, and admitting to the fact that he will indeed accomplish that good, to me of itself is justification for his actions-- not that he needed justifying, because we don't have the status by which to judge him --but more than that: God operates on whole different "level" from us. So much so that most believers even consider the Creator of no regard in what they consider the "natural order of things" and even claim that there are neutral facts, neither good nor bad, such as rock or light or laws of physics; they even include within the natural order of things, luck and Free Will.