"foolish enough to" is correct and usable in written English.
You can use it when you want to describe someone who is particularly foolish. For example, "He was foolish enough to trust the wrong people."
"Nobody would be foolish enough to take this job".
So nobody in Detroit is foolish enough to declare victory.
Few employers today are foolish enough to mandate discrimination.
I was young and foolish enough to do just that.
The fact that Congress was foolish enough to create the fiscal cliff doesn't mean it also has to be foolish enough to drive us off it.
Not that Lendl is foolish enough to blithely speak of change.
I am not foolish enough to think I have made a final decision about marriage.
He will gamble that the Russian people are foolish enough to trade prosperity for nationalistic fervour.
It's hard to believe that Michele Bachmann would be foolish enough to sign this pledge".
Under these circumstances, why would the nominee be foolish enough to reply as Ms. Greenhouse suggests?
Who would be foolish enough to build a boat out of cardboard?
