Why are you forming a whole view of God from ONE verse?
Because it "clearly" shows what God was thinking. There are no verses in the Bible that conclusively say that God has "perfect" foreknowledge. Even verses like:
Act 15:18 "Known to God from eternity are all His works.
Isa 46:10 Declaring the end from the beginning, And from ancient times things that are not yet done, Saying, 'My counsel shall stand, And I will do all My pleasure,'
Do not clearly say God has always had perfect foreknowledge. They show God has certainly planned many things. Acts 15:18 is referring to the saving work of Christ being foreordained. Isaiah 46:10 speaks of God planning the judgment on the nations for their sins.
Jer 18:9-11 And the instant I speak concerning a nation and concerning a kingdom, to build and to plant it, if it does evil in My sight so that it does not obey My voice, then I will relent concerning the good with which I said I would benefit it. "Now therefore, speak to the men of Judah and to the inhabitants of Jerusalem, saying, 'Thus says the LORD: "Behold, I am fashioning a disaster and devising a plan against you. Return now every one from his evil way, and make your ways and your doings good." ' "
God often devises plans based upon the actions of a nation or people. As we see in the above scripture, God was "fashioning a disaster, devising a plan". He did not say "I have always planned this to happen, I knew you would be evil", no, He was forming a plan based upon people's actions.