Last week, Russia fired an intermediate range ballistic missile at Ukraine. The missile, according to nuclear deterrence and missile defense expert Robert Peters, is designed to carry multiple nuclear warheads, sending a clear message to Washington to “knock it off.”  Since the start of the Russia-Ukraine war, America has told Ukraine that it could use the provided weapons only within the “borders of Ukraine to expel the Russian forces,” says Peters, who before becoming a research fellow at The Heritage Foundation served as the lead strategist at the Defense Threat Reduction Agency.  Then, in mid-November, President Joe Biden gave Ukraine permission to use U.S.-supplied long-range missiles to hit targets inside Russia. Ukraine wasted no time in firing one.  Almost immediately afterward, Russia issued a new doctrine on its use of nuclear weapons. As Peters summarizes it, Russia warns “that if anyone conducts deep, penetrating strikes inside of Russia to include using conventional missiles or aircraft or even drones, Russia reserves the right to respond with nuclear weapons.”  Russia also said that a nation that supplied the weapons also could become the target of a retaliatory nuclear strike by Russia.  Russia’s decision to fire the ballistic missile Thursday at Ukraine can be considered a “mock nuclear strike,” Peters says.  Russian President Vladimir Putin “doesn't want a nuclear war,” Peters says. “He doesn't want to fight the United States. But he really, really can't stand that we're giving [Ukraine] these kinds of precise, long-range, deep-penetrating strike capabilities. And he's trying to get us to stop, and he may be willing to use these [nuclear] weapons. It's hard to say.”  Peters joins this episode of “The Daily Signal Podcast” to discuss how the U.S. should proceed in its foreign policy with Ukraine, why a nuclear war would look different than many Americans imagine, and the likelihood that World War III might be approaching.