Ah thanks that position makes more sense to me now, you mean what most people call social democracy, not liberalism as it is understood outside the US? Because at least in britain, libertarian's align with liberals/conservatives against socialists and social democrats.

But to be honest, they are a good example of a flaw in the setup, which is that people tend to define themselves against imaginary enemies that believe everything they do only backwards, rather than naively dispute everything their enemy says. So libertarians are more likely to complain about "statists", than come out in favour of taxes or wars because socialists are against them.