No serious educated or intelligent person believes that. Such a flood within the last 6000 years (which Genesis says is the age of the earth) would have left ample and indelible geological evidence. It didn't.
Oh there were floods alright, just not a worldwide inundation. The lake Missoula ice dam gave way and there is plenty of evidence in Washington state scablands where boulders rode the ice to places they otherwise would not be.
I guess any humans around at the time probably thought it was a world wide flood. Ancient humans had a different conception of the world than we do due to the abysmal ignorance and lack of mobility they necessarily lived with.
Patriotism (and religion) is the last refuge of a scoundrel. Jesus: "Take heed that no man deceive you." Hebrew Roots Judaizer
