Pat Buchanan has speculated that the use of polonium was purposeful to point the finger at Putin:
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*the predictable effect of Litvinenko’s death has been to put a cloud of suspicion over Putin and a chill over Russian relations with the West, one must ask: To whose benefit is the discrediting of Putin? Who would seek a renewal of the Cold War?
Certainly, the oligarchs and robber barons like Berezovsky – many of them now dispossessed of the wealth they amassed in a collapsing Soviet Union, and all of whom have been run out of the country or imprisoned – have the most powerful of motives. They hate Putin and seek to bring him down. And Goldfarb and Litvinenko both enjoyed the patronage of the billionaire Berezovsky.
Surely, rogue or retired KGB agents, passed over by Putin and bitter at Litvinenko, would have a motive: to send a message, written in polonium 210, that this is what happens to those who betray us and Mother Russia. *
My take - even a broken clock is right twice a day - using polonium here is like waving a GIANT red flag saying **the neo-KGB did this **—either Buchanan is right or the KGB doesn’t care. I favor the former but realize the latter is not impossible
Next time I think they’ll use something even more exotic than polonium. I think - though I’m undecided - that terbium would be a good choice, as it has no fewer than 33 radioisotopes of varying stability.
Some intelligence expert on TV said that polonium might have been used because the victim will die slowly and without cure. As such, it is a cruel way to kill somebody, and sends a signal to other who might consider any form of betrayal.
And as P210 is so rare there isn’t a pepper-pot of it in the world (according to expert on c4 news) it signals the power of the killers. It says ‘KGB’ or ‘Putin’ without any of the ambiguity a bullet or toxin like ricin would leave. And the unique Modus operandi leaves wriggle room for Putin’s current wide-eyed innocent act.