[TheOtherHobbes]

Russia splits the West, which is already in some chaos.

Germany is heavily reliant on Russian gas and has been unenthusiastic about sanctions, never mind stronger action. France is being "diplomatic". The UK is an incoherent mess because of Brexit and a mentally ill prime minister.

Also, energy prices. Which happen to benefit both sides.

It's exactly the strategy Russian trolls farms use on social media. Find multiple wedge issues, weaponise them - typically with narcissistic gaslighting and DARVO - inflame grudges and bad feelings on both sides, try to destroy the other side's common identity and purpose.

Putin will have to declare a victory of some sort, but it's likely to be formal annexation of a fairly small region. He'll also be able to blame poverty in Russia on Western sanctions.

The real weapon is the constant psychological and emotional pressure and deliberate confusion.