I've devised a rough-and-ready test to determine whether a person is socialist-leaning, otherwise known as the "Do Something or Nothing" test.
If he is presented with a large-scale economic problem (poverty, mortgage crisis, health care costs, etc.) and advocates the government "do something," he is socialist-leaning. He (implicitly or inadvertently, at minimum) is suggesting that the State can do it better than the market, hence advocates socialism.
If, when presented with a threat to life or property (jihadist attack, urban crime, etc.), he says the government should "do nothing," he is socialist-leaning. He is committed to the view that it is not the government's job to protect the individual against predation, a classic anarchist-socialist fallback position.
I can think of a few contemporary issues that don't fit neatly into this partitioning scheme, the most obvious being the faux-problem of global warming. Here, those who believe this is a problem definitely advocate the governments do something, something big. Perhaps it doesn't fit because it's neither an economic problem, per se, nor an issue of self-defense.
It is an interesting idea, nonetheless. Hmmm... Maybe there are times it is better not to think out loud.