Maybe the hippies are not much of a threat but their philosophy is. Not that humanism and pagan worship will triumph against the Church, but many individual souls could be lost. I wouldn't downplay the danger. When I look at the kids in my neighborhood, I am much more concerned about their being influenced by humanism than by Islam, absolutely no comparison.
I see humanism as the soul in a wilderness. That’s why we saw people like John Lindh being raised in secular-humanist liberal Marin and then being easily swayed into radical Islam. The false nature of humanism is apparent to anyone who does not smoke pot or pine away for Jerry Garcia and they are inevitably seekers.