The famous AbScam sting by the FBI definitely rounded up some corrupt politicians, but the effort that went into tempting and entrapping them just felt like a different side of the same coin. And it cost a lot of taxpayer money.
If you're referring to the Gretchen Whitmer kidnap plot by the Wolverine Watchmen, those dudes had already hatched the plot, performed surveillance, and gathered arms as the FBI informants monitored them and no doubt encouraged them in order to protect their undercover roles. They dropped the hammer when the plot got detailed enough to target Witmer's summer home for the kidnapping, and some less violent Watchmen had simply advocating burning the house down.
You read enough about these militia guys over the years --- the guys who get arrested and the guys who flail in anonymity -- and you wonder if the Wolverine Watchmen would have ever done anything. Or would they have just ranted and bragged and changed their plot a dozen times and kept arguing with each other until the whole thing fell apart. Because there are likely a hundred groups like this having clandestine meeting as we speak. They've always been around, but they are certainly more emboldened now. In many ways it's hard to take them seriously --- they are often really sad and damaged folks engaged in big talk and cosplay. On the other hand, you'd hate to be responsible for them acting on their vows, and law enforcement did nothing despite all the warning flags.