The Bad Catholic blog posted a response not too long ago in which the author pushed back against the claim that if God existed, He would prove Himself to skeptics.
The whole post is here, but this quote is probably my favorite:
“If it takes a miracle to make you believe in God, your belief could only ever be miraculous; never your own. Joe could not reject God after such an event any more than he could reject the weather. And without the possibility of rejection there exists no possibility of Love, a fact which the atheist, in his pious fear and trembling, always forgets, that God’s aim is not simply that we believe in Him — it is that we love Him.”
I’d add that we can’t stop at belief. According to the apostle, to only believe in God is to put yourself on the same level as demons.