The Biden administration’s steadfast support for Ukraine in its fight against Russian aggression has been laudable. But an inordinate and unwarranted fear of “escalation management” has hamstrung American policy.  Administration officials agonize over whether supplying certain weapons to Ukraine will be seen by the Kremlin as somehow escalatory. As a result, the provision of crucial military hardware like tanks, long-range rockets and fighter jets has been held back — only to eventually be provided without much more than grumbling from Moscow.  Even then, however, the administration persists in setting too many constraints on when and where Kyiv can use U.S. weapons for fear of antagonizing Vladimir Putin.   The U.S and its NATO allies have repeatedly crossed Putin’s declared redlines without much in the way of real consequence. Yet American officials are now refusing to allow Ukraine to use U.S.-provided weapons such as ATACMS long-range missiles to strike targets deep inside Russia.  They reportedly fear that Moscow will retaliate directly against NATO member states while downplaying the effect that strikes against Russian airfields, logistics depots and staging areas might have on the battlefield. Never mind that Moscow stepped up its clandestine campaign to sabotage the defense industries of America’s European allies (industries crucial to supporting Ukraine’s war effort), or that German-built Leopard tanks now appear to be operating inside Russia itself as part of Kyiv’s recent Kursk offensive or that Ukrainian drones and jerry-rigged cruise missiles already strike deep into Russia. All available evidence suggests that Putin’s only real redline on Ukraine involves the direct intervention of NATO combat troops in the conflict. Putin seems just as afraid of NATO and the United States as many American and European experts are of him.  Anything below the threshold of direct NATO involvement will likely not provoke a significant response against the United States or its allies — though it could mean more punishing Russian strikes on Ukrainian civilians.  With new long-range munitions on the way to Ukraine, it's well past time for the U.S. to remove remaining restrictions on Kyiv’s use of American-supplied weapons against Russian territory — and encourage America’s allies to do the same.  Right now, Ukrainian forces are allowed to strike back against Russian territory or airspace when under attack, but they’re not allowed to hit Russian bases before, say, long-range bombers take flight to strike Ukrainian civilian targets. Even though many of these bases are within range of American missiles, Kyiv cannot use these missiles to hit them.  There are, of course, legitimate reasons to restrict Ukraine’s use of American weapons — and long-range weapons in particular. Attacks on Russian strategic early warning radars that, among other things, would serve to alert Moscow to an incoming nuclear attack would be unwise. (Kyiv’s homegrown drones have already hit one of these sites.)  These concerns do not justify the blanket restrictions that govern American policy.  A more selective “do not strike” list of sensitive strategic early warning and nuclear command-and-control sites should be possible. Kyiv should otherwise be free to strike legitimate military targets in Russia without the limitations currently imposed by the United States. Dropping most restrictions on the use of American weapons would likely give the United States greater leverage to stop strikes against sensitive strategic targets that don’t involve U.S.-supplied arms and ammunition, whether Ukraine’s weapons or those supplied by other American allies.  American officials can more easily convince their Ukrainian counterparts to apply a “do not strike” list across the board if Ukraine can use long-range American and allied missiles to hit other legitimate targets wherever they may be. Allowing Ukraine to strike into Russia with American-supplied weapons won’t win the war for Kyiv. But that’s not the point of lifting restrictions on their use. Properly targeted and competently executed — and Ukraine’s military has certainly shown the ability to do both — such strikes can reduce the pressure on Ukrainian forces fighting on the frontlines as well as eroding Moscow’s capacity for terror attacks against Ukrainian civilians.  It makes no sense for the U.S. to give Ukraine these weapons and prevent Kyiv from using them to their fullest potential. America should not let Putin’s nuclear bluster deter it from making sure that Russia fails in Ukraine.  Peter Juul is the Progressive Policy Institute’s director of national security.