God does have a right to do anything he wants with us. This, however, is not about what God could do, its about what He promises to do and about how He has revealed Himself. Calvinists assume the premise that all men have been born with a nature incapable of willingly believing in God's revelation of himself due to the Fall of Adam. When Adam Fell it never speaks of such a condemnation. It speaks of labor pains and working the ground and a their knowing both good and evil, but never is this pronouncement of their Total Depravity ever mentioned. I affirm the doctrine of Original Sin, but the idea that men are born incapable to respond to God's message of reconciliation is unfounded. When you come to Romans 9 with that false premise you read into the text that those God is showing mercy must be the Elect ones while those he is hardening must be the Non-Elect Reprobates, but that is never supported in the text. Yes, if they continue in their unbelief they will be destroyed (as Rm 11 also explains), but there is NOTHING in the chapter that even suggests that the hardened ones must be Reprobates who will certainly die, in fact, Paul clearly shows in Romans 11:14 and following that those being "cut off" and "hardened" might be saved...an impossibility for a "non-elect reprobate." In fact, why would he refer to the "reprobate" vessels as those for "common use?" That doesn't sound like its a choice between being saved or condemned, but a choice between being used for a noble purpose or for a common one....i.e. the Jew being hardened, verses Paul being chosen as an apostle. Additionally, if we look at other texts where Paul uses the analogy of a vessel I think we can more clearly see his intent: 2 Timothy 2: 20 Now in a large house there are not only gold and silver vessels, but also vessels of wood and of earthenware, and some to honor and some to dishonor. 21 Therefore, if anyone cleanses himself from these things, he will be a vessel for honor, sanctified, useful to the Master, prepared for every good work. So, its clear from this passage that Paul does believe that men, as vessels, can move from being one of "dishonor" to one of honor. How? "Cleanse Himself." How? "Repent and Believe" in the One who lived a perfect life.