1. Join the nuclear club (i.e., acquire nuclear weapons).
    "The decision of certain powers to go nuclear would have the effect of making endemic regional conflicts totally insoluble." -- Listener
  2. Drop all pretense; take the gloves off; deliberately escalate a personal conflict to unprecedented levels of viciousness.
    "We're not dumb, and that's why we're not going to let up for a second. We know the other side is going to go nuclear soon, and we know that things are going to change. Things have to tighten up. That's the way presidential races are." -- George Stephanopoulos, about 1 month before his candidate, Bill Clinton, was first elected president.
  3. Exert an all-out, balls-to-the-wall effort.
    "[Let's] look at some possible solutions [to ineffective public schools] ... 2. Go nuclear on early reading. The school has done this somewhat ... it's a good start, but 51 percent of first-grade pupils read below grade level." -- Hinkle
  4. Become critical; spin out of control.
    "What's happened here is that a proud (maybe too proud), sensitive (maybe too sensitive) superstar isn't on the same wavelength as his manager and the situation has been allowed to go nuclear. This is a situation that should have been headed off long ago and now fairly begs for some hands-on executive-suite involvement." -- Rapoport

The phrase "go nuclear [on someone]" can also be applied to personal relationships, especially during an emotional meltdown -- one side goes nuclear when they hit below the belt by dredging up long-forgotten, long-forgiven offenses. Fabricated example: "...and then he insinuated that it was all my fault to begin with. So I went nuclear on him. I said, 'Well, at least I'm not living with my mother AND thinking about her as I jerk off.' He totally lost it then, and called me... well, you can imagine."

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