Ukraine: How is 'grey zone' warfare influencing Russia's war with Ukraine?

Existing between war and peace, the 'grey zone' involves acts of aggression that do not quite qualify as a military conflict.

Now, Russia's aggressive invasion of Ukraine has resulted in a war – but before Vladimir Putin decided to invade, Ukraine was subject to highly damaging 'grey zone' warfare.

Elisabeth Braw, a Senior Fellow at the American Enterprise Institute, told Forces News that before the invasion, there was "very little" Russia was doing to breach international law.

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However, she said the presence of Russian troops on the border "significantly weakened Ukraine".

The West, however, has continued to operate in the 'grey zone' against Russia, imposing financial sanctions against the Kremlin.

"The sanctions that have been imposed by the West on Russia go far beyond what are ordinarily considered the sort of sanctions with which a country should be punished," she said.

"This time, it really is about shutting down the Russian economy and thus limiting the duration of this war."