There is also the risk that the investigation will strain future security co-operation, especially if diplomatic cables shared under the ‘‘five eyes’’ agreement with the US are published for political purposes.
The story of what many Trump supporters believe is Australia’s crucial role in a plot against him goes back to an incident in 2016 when Mr Downer, a former foreign minister, was high commissioner in London. In a London bar, Mr Downer met a junior Trump campaign official who told him the Russians were willing to release dirt on Mrs Clinton ahead of the November election.
When anonymous emails on Mrs Clinton were released via WikiLeaks, Mr Downer decided to report the meeting to Australian security services, who shared it with the FBI. This evidence in part led to the Mueller inquiry that embarrassed Mr Trump. He is arguably entitled to question whether the FBI was justified in opening an investigation into his campaign based on that evidence.
The gloves are well and truly off in US politics and nothing is surprising now that Mr Trump faces an impeachment inquiry over an alleged attempt to influence Ukraine to find dirt on potential Democrat candidate Joe Biden. But the idea that Mr Downer or Australia was somehow part of a conspiracy to help Mrs Clinton in 2016 is delusional.
Surely Mr Trump’s aides have told the President that Mr Downer, as a conservative politician, was anything but hostile to him and as a senior diplomat of a trusted ally he would not make this stuff up.
It is laughable that Australia’s security agencies, then answerable to the Liberal government, were trying to interfere against Mr Trump. They were just doing their job under the ‘‘Five Eyes’’ agreement to share relevant information with the US.
Yet Mr Trump has urged his Attorney-General, William Barr, to ‘‘look at Australia’’ along with other countries to get to the heart of why the FBI was moved to act.
It is important not to give way to irrational suspicion about Mr Trump and there is no need to antagonise him. But if he believes Australia is after him, his judgment is way off. This investigation will probably go nowhere, especially as the impeachment inquiry heats up. But it will be galling if Mr Trump hints on the campaign trail that Australians were conspiring against him.