President Joe Biden has given permission to Ukraine to strike inside Russian territory with American munitions, though he has restricted their use so Kyiv can only hit targets over the border close to Kharkiv after Russia made significant advances around the city in the northeastern part of the country close to the Russian border, two US officials told CNN.
I can understand Russia's reticence, given that the U.S. is always foaming at the mouth to do something horrifically evil and aggressive, and the U.S. will fucking consider a pigeon landing on a NATO commander's head to be a Russian plot. But you're right in that Russia in hindsight should have gone more tit for tat.