This is fun. Michele Bachmann, on the campaign trail today, offered what seems to be a new explanation for her previous work as a lawyer for the Internal Revenue Service, something that has drawn some ire from the right.

Her explanation: She worked for the IRS as a kind of secret anti-tax mole whose mission was to get to know the place in order to better undermine it later. As she put it: “The first rule of war is `know your enemy.’”

This explanation seems a bit at odds with descriptions of the episode she’s given on previous occasions, when she’s said her anti-tax fervor was the result of her work for the IRS. This version on the trail explains her work for the IRS — which spanned four years, from 1988-1992 — in a way that will be more acceptable to hard-core anti-tax conservatives.

The moment was captured by the liberal group American Bridge, which sent over the footage:

Bachmann, speaking at a rally today in South Carolina, said:

“We change the economy by changing the tax code. How many of you love the IRS? No! It’s time to change it. I went to work in that system because the first rule of war is ‘know your enemy.’ So I went to the inside to learn how they work because I wanted to beat them.”

In recent days, Bachmann has been taking some heat from Ron Paul supporters for her IRS work, and more broadly, Rick Perry’s entrance into the race will mean the competition for conservative voters will now be more intense.

Bachmann has previously offered a somewhat differing account of her work at the IRS, which tax experts have said was akin to being a tax collector. According to the Wall Street Journal, Bachmann has said in the past that her work at the IRS informed her anti-tax views. In 2006, the Journal says, Bachmann claimed that she undertook the study of tax law in order to “be faithful to what God was calling me to do through my husband.”

Bachmann’s Congressional Web site describes her work for the IRS this way:

Before holding elected office, Bachmann worked on hundreds of civil and criminal cases as a federal tax litigation attorney. Through her experience as a tax attorney, Bachmann came to understand firsthand the need to simplify the current tax code and reduce taxes on families and small businesses.

That seems to suggest that Bachmann’s work at the IRS was what persuaded her of her current anti-tax views, and there’s no hint in that description that she went to work for the IRS out of any secret plan to undermine the agency or the tax system from within, as she claimed today.