Paul Wood wrote for the BBC about Russian involvement in Donald Trump's campaign - and whether the FBI is over its head and possibly fumbling the investigation:
The BBC has learned that US officials "verified" a key claim in a report about Kremlin involvement in Donald Trump's election - that a Russian diplomat in Washington was in fact a spy.
So far, no single piece of evidence has been made public proving that the Trump campaign joined with Russia to steal the US presidency - nothing.
But the FBI Director, James Comey, told a hushed committee room in Congress last week that this is precisely what his agents are investigating.
Stop to let that thought reverberate for a moment.
"Investigation is not proof," said the president's spokesman.