WE have long known that Donald Trump lies. Writing in the New York Times this week, journalist David Leonhardt provided an incomplete reminder list of some of the things Mr Trump has lied about.

Among them were Barack Obama’s birthplace, Mr Obama’s phone tap, the US unemployment rate, the murder rate, voter fraud, September 11 and Mr Trump’s own groping of women. I did say the list was incomplete.

Just as we know Donald Trump lies we know too that habitually when under pressure he lashes out.

Lies and lashing out have always been his political modus operandi. When these don’t work, then there is always the old fall-back strategy of creating some other news story or crisis elsewhere in order to switch attention away from the issue that currently pains Mr Trump most.

“Kremlingate” as it has now become dubbed, is clearly what troubles the President most right now. Hardly surprising, then, that FBI director James Comey was on the receiving end of both barrels from the Trump administration this week and found himself fired.

While Mr Trump tries to dress it up differently there is little doubt that Mr Comey’s sacking has everything to do with the Russia inquiry. Few doubt the FBI chief was kicked out because he was leading an active investigation that could bring down the President.

Mr Trump’s explanation that he fired the FBI director because he bungled the investigation into Hillary Clinton’s email is so implausible as to be embarrassing. Then again this is a president as impervious to embarrassment as he is to calls for honesty and transparency.

The simple indisputable fact is that with congressional Republicans continuing to resist any serious investigation, Mr Comey’s inquiry was the only aggressive effort to get to the bottom of Moscow’s ties to the presidential election campaign. According to congressional officials, just days before he was sacked, the FBI director asked the Justice Department for a significant increase in resources for the bureau’s investigation into Russia’s interference in the presidential election.

What played out this week was yet another sharp reminder that these are dangerous times in the United States. By firing Mr Comey, President Trump has cast grave doubt on the viability of any further investigation into what could be one of the biggest political scandals in the country’s history. The gross self-interests of a president whose vanity knows no bounds has seemingly rendered the country’s majority party oblivious to its responsibilities to its constituents and the Constitution of the United States.

There is something else too that this week’s events have also highlighted. They have once again reinforced the inescapable sense that Mr Trump continues to act like he has something to hide over the Russia inquiry. The sacking of Mr Comey smacked of just another act of political self-preservation.

These factors are in themselves reason enough to redouble efforts to mount an independent investigation of the Trump administration’s links with Moscow. The evidence garnered so far makes such a full investigation imperative. In the last few weeks alone it’s become clear, among other things, that a federal grand jury was investigating Michael Flynn, Mr Trump’s first national security advisor, who had not disclosed payments he had received from Russia and who lied about his conversations with the Russian ambassador. We have learned too that the FBI had obtained a Foreign Intelligence Surveillance Act warrant to monitor Mr Trump’s campaign advisor Carter Page, which means he was suspected of being a Russian agent. Then there is the small detail of Mr Trump’s one-time campaign manager, Paul Manafort, having received millions of dollars from a Russian oligarch close to President Vladimir Putin to influence American politics. Most recently Mr Trump has had to hire a law firm to fight allegations that he has business links to the Kremlin.

The question now is what happens next over Mr Comey’s departure and the thorny issues Kremlingate has again thrown up? Until recently, most Republicans have rejected the idea of an independent commission or special prosecutor to investigate the potential links between President Trump’s campaign and Moscow. It can only be hoped that Republicans in Congress will now finally be ready to confront the White House over the Russia imbroglio.

Yesterday the turmoil continued with unconfirmed reports that Rod Rosenstein, the deputy attorney general, had threatened to quit after he was blamed for the FBI chief’s sacking.

Another question concerns the next moves of the FBI itself. Will the bureau pick up where its former director left off and continue its investigation, or will it capitulate with the White House and keep its head beneath the parapet? Much depends on who the next director is, and while the obvious choice to lead the FBI until a permanent director is selected would be Andrew McCabe, the current deputy director, the ominous signs are that the administration has other ideas. This is indicative of how much Mr Trump is determined to maintain control of the FBI and keep a lid on any Kremlingate investigation.

More than anything else the firing of Mr Comey should act as wake-up call to many in America and beyond who were perhaps sliding into a state of complacency over the character and direction of the Trump presidency.

Much is at stake here. Republicans must not allow Mr Trump to go unchallenged on this. They must ensure that he cannot simply nominate any FBI director he wants. They must also resist pressure not to appoint a special prosecutor, or to convene an investigative body into links with Moscow. Should they fail to do both these things, Mr Trump will simply read it as a green light to do as he wants. As The Atlantic Magazine’s Ron Brownstein observed this week, Mr Trump’s “appetite for shattering democratic constraints is only likely to grow”.

If anything good has come of Mr Comey’s firing, it’s the potential it has brought to again kick-start the semi-dormant conversation about the vulnerability of public institutions in the US. A sense of accommodation over the Trump presidency was definitely setting in. The events of this week are a stark reminder of the price such complacency brings.