Summary
Two days later, when President Barack Obama warned that there would be "costs" for invading Crimea, the Russian forces were already in place and the intervention was nearly a fait accompli.
The Russians are thought to have had roughly 15,000 troops in Crimea when the crisis began, and quickly added about another 5,000, mostly special operations troops.
Because the troops didn't have Russian insignia, there was a thin veil of deniability, which the Russians exploited.
This "deniability" was maintained by Defense Minister Sergei Shoigu, who said on March 5 it was "complete nonsense" that Russian troops had invaded Crimea and that he had "no idea" how Russian military vehicles had gotten there.
Finally, Putin prepared a rationale for his intervention – along with the attendant propaganda. He insisted he was acting to protect Russian citizens and Russian speakers in Crimea.
The well-organized Crimea operation also suggests improvement in the quality and training of the Russian military.
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