Vladimir Putin justifies the aggression against Ukraine as necessary to protect the Russian-speaking minorities, whose rights are being brutally violated by the Ukrainian authorities. The Kremlin's language quite consciously follows the so-called Responsibility to Protect (R2P) theory, adopted by the UN in 2010s and postulating the need to interfere in the internal affairs of other nations if their governments fail to protect their own people from genocide. Today, R2P is Putin's key rhetorical lever which he uses to influence both domestic and international audiences.
In a piece for War on Rocks military review John Reid, an active-duty Air Force officer in the US Special Operations Command Europe, writes about the practice of using R2P to justify military aggression and the need to adjust this doctrine to deny authoritarian regimes a pretext for attacking their neighbors.