1 - Russia is tactically taking advantage of US caution. They amassed their forces on the border with Kharkiv in the wide open and used the head-start to launch an offensive there.
2 - At this point, the US has realized that Russia isn't going to come to their senses without a more decisive defeat. If anything, Russia is doubling down on their attack wish-list.
3 - Most importantly, Russia is launching espionage based attacks affecting Czech Republic, Estonia, Germany, Latvia, Lithuania and Poland.
At this point, Russia has broken the red lines, and so NATO is opening theirs in a tit-for-tat fashion.