John Noonan, a former national security adviser to 2012 Republican presidential nominee Mitt Romney and 2016 GOP contender Jeb Bush, Wednesday, broke down the many reasons current party standard-bearer Donald Trump should not be allowed anywhere near the nuclear arsenal. MSNBC's Joe Scarborough revealed that Trump had thrice asked during a high-level policy briefing several months ago why the U.S. couldn’t use nuclear weapons. “Three times he asked, at one point, if we had them, why can’t we use them,” the former lawmaker turned talk show host said during a discussion with former National Security Agency director Michael Hayden. The exchange sent Noonan into a 20-point Twitter rant that echoes some of the complaints voiced by a growing chorus of conservatives now vowing to support Democratic presidential nominee Hillary Clinton. 15. The power is there to kill millions. Permanently alter the geopolitical landscape. It is a sacred, sobering responsibility. — John Noonan (@noonanjo) August 3, 2016 His worst fears poured out in a series of cautionary missives about the fragile nature of nuclear deterrence. 7. The nuke triad, which Trump doesn't have a clue about, has been the single greatest contributor to global peace for decades. You heard me — John Noonan (@noonanjo) August 3, 2016 The most terrifying thought: A capricious decision might one day ruin us all. 14. But imagine having to turn launch keys not knowing if we were under attack or if it was b/c foreign leader said a mean thing on twitter — John Noonan (@noonanjo) August 3, 2016 “Imagine having to turn launch keys not knowing if we were under attack or if it was [because a] foreign leader said a mean thing on Twitter,” he warned. Contact Rojas at warrenrojas@rollcall.com and follow him on Twitter at @WARojas . Get breaking news alerts and more from Roll Call on your iPhone or your Android.