(CNN) It is a very bad idea -- for all concerned.
Yet the drumbeat towards another war in Ukraine is amplifying itself, taking on a life of its own, in a huge, high-risk maneuver by either the Biden administration or Moscow, or both.
"I really don't know where this all came from," is a phrase I have heard Western officials sigh multiple times over the past months.
Yes, Russia's military is on the move, and massing in perhaps larger numbers than in the other years when we have seen similar posturing.
Yes, a source familiar with the intelligence tells me there are indications that Russian officials are not just theorizing about an invasion but are actually working out how they might enact one, if ordered to do so.
But some of their positions are more than a hundred miles from Ukraine's border. And the reasons why Russia really wouldn't want to occupy any more of its neighbor's territory are the same as they have ever been.
Firstly, this would not be the invasion of Ukraine, but the re-invasion. Ukraine has already been invaded twice, even if Moscow pretended that the "little green men" who took Crimea weren't theirs, and that the "concerned locals" who swarmed Donbas had purchased all their armored personnel carriers in army surplus stores.
Part of Russia's problem is that these were incomplete moves, carried out quickly and without a full plan for the future. Renewed Russian action could finish what they left undone and bring longer term benefits to Moscow. But their incompleteness is also a daily reminder that such conflicts are full of unknown unknowns which disrupt plans.
Russia's critics and admirers alike are bound by a rare unity when they see the Kremlin's every action as purposeful, and guileful. But that is rarely the case.
After it barged into Crimea in 2014, Moscow was left without a land corridor linking the peninsula to the Russian motherland, and only finished in 2018 a thin bridge across the Kerch Strait for utilities and supplies.
Its de facto invasion of Donbas ended in 2015, yet Russia still props up a chaotic and messy separatist movement there. This rump of mercenaries and outliers come at a cost, with little benefit; Moscow is unlikely to profit from the area, since it is not the industrial heartland it once was.
The arguments that the Kremlin needs a land bridge to Crimea and a more certain status for Donbas are often central to explanations for why it may invade Ukraine a third time in eight years. But most military options would come at extraordinary cost.
At its most minor, Russian action could involve "normalizing" the country's grip on the Donbas region by sending in Russian troops to lock down their control of the area, or even to slightly widen its buffer zone against the rest of Ukraine. There could be benefits from that, but it would likely trigger costly sanctions and formalize Moscow's expensive position as the battered region's sponsor.
Other analysts suggest that a narrow land corridor along the Azov Sea, through the city of Mariupol, would reduce the cost of maintaining energy and water supplies to Crimea, and could be easily achieved through an amphibious landing on the Azov Sea coast. Yet a thin strip of land running along the shoreline would be hard to defend and less profitable as a commercial supply route if it was constantly at risk of attack from Ukrainian forces.
The next option passed around the cottage industry of Ukraine war-gaming is a wider invasion. Under this scenario, Russia might push all the way up to the Dnieper River, taking Kharkiv, Poltava and even breathing down the neck of the capital Kyiv.
But this is where the theorizing gets a bit silly. I heard one reputable analyst speculate about the invasion of all of Ukraine. ALL of it. A country slightly larger than France, from Luhansk in the East to Lviv in the West. That's more than a 16-hour drive for one of Russia's newest tanks -- running flat out, at its highest known speed -- with nobody in its way, and no stops to refuel.
The idea of occupying a large area of Ukraine may have seemed possible in 2014, but after seven years of war, Ukraine is noticeably short on nostalgia for its former Soviet neighbor.
An occupation would be bloody, cost many Russian lives, require hundreds of thousands of Russian troops, and likely be an embarrassing reminder to the Kremlin, as its forces become overstretched, of how decrepit its military was just over a decade ago, before their swift modernization.
Sanctions would also damage, if not cripple, the Europe-facing parts of Russia's economy.
Even a small invasion is really a bad idea for Moscow.
Proponents of how likely an invasion is often remark that Putin is not a rational actor, arguing that he is prone to unpredictable sweeping moves. They note that, as a superannuated autocrat without any checks, balances, or real elections to worry about, he is free to decide anything, at any hour.
The Kremlin chief's decision-making has long been deliberately opaque. And after 21 years at the helm and nearly two years in a Covid-19 isolation bubble, where his interactions are significantly limited, it is possible to imagine the information he is getting is far from balanced.
Which is why the Biden administration's decision to amplify the likelihood of an invasion is so intensely risky.
There are clear warning signs -- and possibly starker undisclosed intelligence -- to support the possibility of an attack. Perhaps ensuring your allies are aware and ready for it is better than staying silent and seeming unprepared.
But by sounding the alarm so loudly, the White House has given Putin a choice: Act now, or make it seem like you gave in to pressure from the West.
And surely that is something that would be tough for the Russian leader, who believes his country was starkly humiliated at the end of the Soviet Union, to take?
Forcing him to make such a choice cannot have seemed the best option to CIA head and former US ambassador to Moscow, Bill Burns, or the other students of Russia policy in the Biden White House. You have to hope they know something everyone else does not.
Have they calculated -- or learned -- that Putin simply cannot afford to invade Ukraine again? Or have they determined that the invasion is inevitable?
If there is any doubt, this US operation to raise awareness of the risk could tip the scales and force Russia to do something it probably knows will end badly.
And so now -- given the non-starters Russia requested at its talks with the US in Geneva and the apparent stalling, if not collapse, of those negotiations -- Ukraine is stuck, facing an appalling eight week-wait while the ice remains hard enough to allow tanks to roll across the Russian border. After that the mud will set in, and along with it another summer of mild tension.
Perhaps the long-term gain of these months of febrile speculation and shrill panic will be judged to be shoring up NATO and Europe against the threat of Russia, and proving to Moscow that the costs of any further adventurism would be unpalatable, or at least met with a united front.
Perhaps the Biden administration simply wanted to show Russia that the US is back in Europe, reversing the Trump years' cosiness with Moscow.
But Ukraine, which has already endured the loss of more than 10,000 people in this war, has found itself at the center of a high-stakes game of brinkmanship, with the US-Russia relationship front and center. People are once more paying attention to its plight, but it risks looking like an afterthought, trapped in the middle as Washington and Moscow duke it out.
Putin has the global attention and US engagement he perhaps craves. But with the chips laid down, all in, this huge diplomatic gamble risks a major land war in Europe.