Does Trump's nuclear testing raise the stakes - or are we already in an arms race?

President Trump announced via social media that the US would begin testing nuclear weapons immediately, citing other countries' testing programs, though the White House has not clarified whether this means testing actual weapons or delivery systems. Most nuclear policy experts interviewed expressed deep concern that such testing could trigger a domino effect among nuclear powers, particularly Russia and China, potentially accelerating what many believe is an emerging three-way nuclear arms race. The announcement comes amid heightened global nuclear tensions, including conflicts involving nuclear states and the impending expiration of the last US-Russia arms control treaty in early 2026.