Britain has been irrelevant in Ukraine's crisis. If it leaves the EU, it will only become more insignificant.
Britain's Foreign Secretary William Hague turned up in Kiev on March 3, stating that the situation in Ukraine is the biggest European crisis of the 21st century. Historians can argue about whether Britain realized that too late, or better late than never. Because by March 4, Russian President Vladimir Putin already seemed to have achieved the optimal level of Western humiliation without over-extending his position: He had done enough to make his point about Russian influence in the Ukraine by sending troops into Crimea, but avoided any genuinely tough Western response, which a full-on invasion of eastern Ukraine might have triggered.