Anyway, it's not because the UK and USA have done it earlier that it's behavior that should be tolerated, or worse, promoted.
My thoughts exactly.
That is an argumentation I've seen a lot. The US does X, so Russia can do X too. Even if the first part is right, that is not how laws are supposed to work.
It depends on how the people see these troops. If they see them like oppressors, they will be oppressors. In Crimea, different thing happened. They just didn't see them in that way. I think.
That is not the point. Even if we assume that a) Crimea wants to join Russia and b) Crimea wants Russian soldiers as protection, that doesn't mean the Russian intervention was right. Putin could have used diplomatic pressure to achieve these things. He could have trippled the gas prices. He could have let elections happen in Ukraine and support a constitutional change that allows for Crimean independence. He could have involved international organisations. There were a lot of options and he chose the one that he knows everyone will understand as a massive disruption of international stability.
If, however, that economic and social stability vanishes as a result of an economic collapse induced by Western sanctions, there is no reason for Russians to support Putin or United Russia. If the Russians came anywhere close to where they were in the 1990s the whole thing would come down like a house of cards.
If Putin's government falls, no one can guarantee that pro-Western liberals will take charge of the country. In fact, it may result in more radical politicians being voted into office or seizing power. None of Russian opposition leaders enjoy any significant popular support outside of Moscow.
I remember, when Putin first became president, a lot of "experts" were arguing that Russia needed "a strong hand" for a time, as a transition into democracy. Yeltsin obviously was not strong, and people at the time were worried about the likes of Zhirinovsky. Our chancellor praised Putin as a great democrat.
Now I'm sure if Putin would fall and Russia would experience a bad economic downturn, there would be far worse and more radical people coming into power. I don't think Russia would fall apart, it might become more nationalistic instead. But Putin is looking much more authoritarian now than back then, and it's not getting better.
Apologies if I'm terribly wrong (I don't live in Russia so what do I know?) but it seems to me like the main reason people in Russia vote for United Russia and are happy with them being in government despite rampant corruption and disregard for human rights is that they have ensured that Russia is economically and socially stable.
This was also important in regards to the Crimea referendum. The average income in Russia is way higher than in Ukraine. Compared to Ukraine, Russia has developed much better economically since the dissolution of the USSR. Pensions will be much higher (and apparently there are a lot of pensioners living in Crimea). State employees will get triple or more as much in wages.
I haven't got the numbers, but that might have been a factor too.