I agree with you that there seems to have been some divine providence behind the creation of this nation -- certainly in the way that such different geniuses could be brought together in one time and place.
However, the men who put it together were not universally men who "turned from wicked ways" -- at least not as modern religious conservatism would define "wicked ways." For that matter, in Second Chronicles 7:14, God was responding to Solomon, another divinely-guided rulers who seemed far from perfect morality.
(For that matter, it's an open question as to whether that passage in the Bible refers to nations in general or only the kingdom Solomon ruled.)
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This is not surprising. Although we may all strive for perfection, we are human.
I don't think it refers to a nation at all.
If it referred to Solomon's Kingdom, it should read "If My people, which are called by their ancestor Israel's name..."
I think it refers to the People of God; we Christians tend to appropriate Him, and we think with good reason, knowing that taking His Name in vain is a grievous wrong.
I think any nation, comprised largely of the People of God, who themselves "humble themselves, and pray, and seek [His] face, and turn from their wicked ways," will enjoy the blessings of the remainder of the verse.
As the righteous few suffer the temporal judgements laid upon the unjust many, while waiting the blessings of eternity, so also the unjust few enjoy the temporal blessings poured upon the righteous many while waiting eternal destruction.