Russia has has their eyes on Ukraine and Crimea for a good minute, and their presence of Russian troops along the Ukraine/Russian border doesn't really ease anyone in the terms of a possible conflict.
This could just be a big political shit test Putin is doing on Biden to see what he can get away with. Seems like everytime the U.S. gets a new president, someone wants to whip their dick out politically or show their ass militarily.
Putin does have the right to build troops along his side of the the border of any neighboring country, but if a certain country feels threatened by such actions, then it is also their right to react appropriately.
Putin can make claims that he has no interest of invading Ukraine all he wants, but with the mobilization of troop and equipment along the region doesn't help his claims at all, especially with the beef Ukraine and Russia has has in the past...yikes.
History doesn't repeat itself, but it does have a familiar tone. All it takes is one prick to invade a country, convince himself that he's now powerful enough to do it again because nobody challenged his power, and then do it again to a neighboring country. Which is why it's important for NATO and allies to remain vigilant and have a presence to keep an eye in case anything escalates further into something much worse.
I disagree with U.S. troops in Ukraine but not around Ukraine. Since you know? "We got the right to mobilize and drill." Isn't that right, Putin?
But I do see Putin's reasons for not wanting Ukraine to be part of NATO (they wouldn't have asked to be in NATO, if you weren't such a fucking prick in the first place...) because Ukraine kinda adds a "buffer zone" between Russia and NATO allies. If Ukraine does become part of NATO, then they'll can do militarily exercises right at Russia's doorstep, but he fucked up that possibility by making it look like he's preparing for large military action. Putin should have thought of it this way: "I don't have Ukraine, but at least they (NATO) don't either."
I really hope this doesn't boil-over into a literal 3rd World War, but only time can tell.
By the way: Russia is acting as the aggressor here. Even if they "had no intention of invading Ukraine" then they wouldn't have made their military movements look like such, which would have saved them the headache of dealing with this in the first place.