Deciphering Steyn

Mark Steyn is appalled that a pedophile in Britain is getting Viagra via the taxpayer-funded National Health Service. He quips:

I think this is what those heartless American insurers would call a pre-existing condition.

I cannot figure out what he is trying to say. In America, insurers routinely pay for Viagra. Is he suggesting that insurers would deny his claim because he's a pedophile? Are insurers allowed to deny coverage because of a criminal conviction? Or does he have some other meaning that I am missing?