The trigger for the fresh violence in Kiev appears to have been Tuesday's parliamentary session.
The speaker of the Rada (parliament) Volodymyr Rybak refused to allow a debate on the opposition's move to amend the constitution. Thousands of protesters had descended on the Rada for the session and, as they pressed in on the riot police protecting the parliament, fighting broke out.
What happened next was merciless on both sides. At least 25 people died, more than 200 ended up in hospital.
This no longer seems to be a democratic argument over Ukraine's relationship with Russia. It is a violent power struggle. The violence is contained - and mostly takes place in 4sq km in central Kiev - but the determination of the most active protesters should not be underestimated, nor should President Viktor Yanukovych's determination to survive.
It's unlikely that any leader of a Western European democracy would still be in their post if similar events had happened in their country.
But although the violent protesters, many inspired by far-right politics, are now focused on revolution, their numbers are small. They alone could not overthrow the government. But what makes this crisis so serious is the quiet support that many in western Ukraine, particularly in Lviv, are giving to the violence.
It means that a split between eastern Ukraine and western Ukraine is being openly discussed, even though few people say they want that. It would allow those in the east to remain close to Russia and it would allow Russia to take Crimea back under its wing, which is hugely important to it historically and strategically.
But a clean split without further bloodshed is not that likely. It's unclear where any border would be. So there are strong reasons for avoiding a split as it may lead to civil war.
The parliamentary opposition and the government will at some point need to negotiate a settlement if war is to be avoided, but opposition leaders Vitaly Klitschko and Arseniy Yatsenyuk know that if they make too many concessions, that would be seen by hardline protestors as betrayal.
This is a like violent game of chess, and nobody can see enough moves ahead to know what the outcome will be.