It may be worth it from a message standpoint. Remember that the EU's been complaining about how Estonia is part of the EU and it's all for one and one for all, and stop picking on our membership. This sends a message that Putin knows that with the total oil lock he has on Europe (and Europe's utter failure to stand up for themselves) that he can pretty much do whatever he wants and the EU's going to pretend that nothing happened, just like they do whenever another journalist gets mysteriously poisoned. And remember that this is good practice for Russia too. NATO may be able to practice defense, but Russia gets to practice offense.