Ukraine's State Border Guard Service said its personnel came under attack at 5 am local time
Russia's invasion of Ukraine is following an early progression many military analysts had predicted, with an intense barrage of missile attacks launched from afar to destroy Ukraine's airfields, air defenses and control systems.
A full picture of what's happening on the ground is harder to assemble in real time, but it appears that Putin has opted for a large campaign aimed at achieving regime change, rather than a more limited take over of the separatist Donbas territories he has recognized as independent.
According to the US, Russia had built up a force around Ukraine numbering between 150,000 and 200,000 troops by the time President Vladimir Putin gave the order to move early on Thursday.
Ukraine's State Border Guard Service said its personnel came under attack at 5 a.m. local time in five provinces ranged around the country's north eastern borders, as well as through Donbas and occupied Crimea, to the south.
Russian tanks were reported to have reached the outskirts of Ukraine's second city, Kharkiv, by mid morning, and to be fighting in the Kherson region just north of Crimea. By early afternoon the Interior Ministry confirmed a Russian air assault to capture Hostomel airport, just outside the capital, Kyiv.
What happens next, according to the Moscow-based defense analyst Pavel Felgenhauer, is best understood from Putin's stated goal to "demilitarize" rather than occupy Ukraine, a nation of 41 million that has a territorial expanse similar to that of France.
"That means the Ukrainian armed forces should be totally disbanded, weapons liquidated and Ukraine turned into a buffer zone where Russia can do what it wants without any ability of Ukraine to resist," said Felgenhauer, a veteran military analyst with the Jamestown Foundation, a U.S. think tank. "Putin was very specific, territory issues come second."
That, in turn, means targeting the Ukrainian armed forces mostly in Donbas, where Russian forces are likely to engage from the front and surround them, Felgenhauer said. Russia cannot afford a drawn out engagement, but rather "it will be a Blitz, a Blitz Krieg," he said.
That's a view shared by Ben Hodges, a retired U.S. General and former commander of the U.S. Army in Europe. Taking -- rather than threatening -- Kyiv, a city of 2.8 million, would risk months of urban warfare and require all the manpower Russia has available. In U.S. experience, he said, taking one hotel-size building requires a battalion, or 700-800 men.
"I just don't think it's feasible," Hodges said on the margins of the Feb. 18-20 Munich Security Conference.
There's little doubt Putin has his eyes on more than just the separatist territories, according to Mathieu Boulegue, a specialist in Eurasian security and defense at the London think tank Chatham House.
In Putin's pre-war address to the nation, said Boulegue, he spent less time talking about stopping further NATO expansion than what he saw as the illegitimacy of Ukraine as a state, cobbled together -- in his account -- by a series of arbitrary Soviet-era decisions.
"It was the way he was talking about Ukraine almost like it was a Lego set," Boulegue. "He was making the case to Russians that by going in he would be righting a historical wrong."
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