House Democrats are hours from crossing a somber point of no political return as they get set to roll out articles of impeachment Tuesday accusing President Donald Trump of abusing power and obstructing Congress.

The momentous step towards making Trump only the third president to be formally impeached in nearly two-and-a-half centuries of US history comes in a tumultuous third year of his term and only 11 months before the next general election.

"This is not a happy day," said House Foreign Affairs Committee Chairman Eliot Engel, one of several key Democratic leaders expected to make a formal announcement on Tuesday morning. "But I think we are doing what we have to do."

Democrats have accused the President of abusing his power by withholding nearly $400 million in US military aid to Ukraine and the prospect of a visit to the Oval Office by new President Volodymyr Zelensky in order to coerce the former Soviet state into investigating a potential 2020 foe Joe Biden. Such conduct they say is a worthy of impeachment because it amounts to bribery, puts Trump's own political goals ahead of America's national interests and effectively invited a foreign power to interfere in a US election.

"The scheme by President Trump was so brazen, so clear, supported by documents, actions, sworn testimony, uncontradicted contemporaneous records that it's hard to imagine that anybody could dispute those acts, let alone argue that that conduct does not constitute an impeachable offense or offenses," said Barry Berke presenting the case against Trump for the Democrats in a Judiciary Committee hearing on Monday.

Republicans have struggled to counter the facts laid out by witnesses drawn from ranks of foreign policy and military officers. But they deny Trump's did anything wrong at all, let along anything that reaches the level of impeachment.

"It's a disgrace. A hoax," the President said at the White House on Monday, without bothering to counter any of the evidence.

The top Republican on the House Judiciary Committee, Rep. Doug Collins of Georgia, meanwhile accused House Speaker Nancy Pelosi of rushing to impeachment -- with expectations that Democrats will hold a full House vote on the issue next week.

"The speaker of the House after hearing one day of testimony in the Judiciary Committee, said, 'Go write articles.' Facts be damned," Collins said.

Democrats counter that Trump has denied more than 70 requests for evidence and blocked testimony from key officials, giving them no choice but to declare that he obstructed Congress in its lawful oversight function. They have elected not to launch legal challenges to compel testimony that could drag on for months.

The prospect of impeachment represents the most serious political reverse yet for Trump. Yet given his habit of skipping past political scandals -- again on display Monday as the Justice Department inspector general debunked his conspiracy theories about the FBI -- it's unlikely he will rein in his convention-busting behavior.

One day, Trump may pay a price for his constant attempts to test the limits of his power, for lying about proven facts at a historic clip and ignoring the convention of his office. Such a reckoning could come at the next election. But such has been Trump's success in reshaping the narrative of the scandals besetting his presidency, it's no sure thing that voters who propelled his victory will side with the Democrats.

It may be that only history can record a damning verdict against the President -- though for future generations the whirl of confusion on days like Monday will be difficult to understand.

For now, the President is pioneering a new theory of political office -- if you never admit to being caught in the act, it's very hard for adversaries to make you pay the consequences. It's an extension of Trump's lifelong mantra to never admit wrongdoing and never apologize that sustained him through all kind of scrapes in the rough knocks world of business.

How else to explain his judgment that the rough log of a smoking gun call with Ukraine's President in which he is shown as asking for a quid pro quo "favor" is "perfect?"

Of course, within two weeks Trump is likely to be only the third American president to be impeached -- a black mark that is certain to form the first line of his eventual obituary.

But he's unlikely to hold his head in shame. In fact, he's bound to tout almost certain survival in a Senate trial as the ultimate triumph over a political swamp the never wanted him as President and has tried to topple him ever since.

Trump's 24-hour a day assault of conspiracy theories, alternative facts and political attacks on his opponents has left the Washington system struggling to cope.

It's as if he has worked out that as long as his incessant assault on the senses keeps gathering pace, no one will be able to keep up with the magnitude of his malfeasance.

Of course, Trump could not do it alone.

An underappreciated wrinkle of Trump's his political genius is his ability to assemble an uber loyal band of sidekicks and henchman willing to harness their reputations to his survival.

His band of brothers reflect his domination of the Republican Party and his success in harnessing his connection with the grass roots as a lever to control lawmakers in Washington.

Now the President has dispensed with the "adults" -- military, national security and political professionals once seen as restraints on his wildest instincts -- he's left with the loyalists who will fight alongside him whatever happens.

Trump defenders in Washington seem certain to frustrate Democrats' hopes of ousting him from office however incriminating the evidence.

Once again Monday, Attorney General William Barr played the role as chief spinmeister to redirect a narrative that's damaging to the President -- just as he did when creating an inaccurate interpretation of the Mueller report that shielded Trump.

Barr rejected the finding of Justice Department Inspector General Michael Horowitz that the FBI showed no political bias in opening a probe into his 2016 campaign's links with Russia.

In effect, the report exonerated Trump's enemies, such as former FBI chief James Comey from the President's claim that they conspired against him. It also debunked the idea that the probe was opened based on findings of the Steele Dossier, a document funded partly by Democrats that said Trump was compromised by Russia.

Barr chose to focus on critiques in the report that FBI lawyers made errors in filing applications to a special court for wiretaps on former Trump foreign policy adviser Carter Page.

"The inspector general's report now makes clear that the FBI launched an intrusive investigation of a US presidential campaign on the thinnest of suspicions that, in my view, were insufficient to justify the steps taken," Barr said.

Even more incredibly, Barr enlisted the prosecutor that he has asked to look at similar material, John Durham, to put out his own statement registering disagreement with Horowitz.

The move raised immediate doubts about Durham's independence and suggested that Barr is leaning on his investigation to produce a finding more palatable to the President.

It also established a new political narrative for Trump's propagandists in conservative media -- that the watchdog report is merely a distraction and it's the Durham report that really matters.

It would not be the first time that Barr has seemed to act more as Trump's lawyer than the independent figurehead of US justice -- a role to some extent walled off from the White House -- that the attorney general is traditionally seen to occupy.

Barr was not the only Trump lieutenant who rode to the President's defense on Friday.

The President's allies in the House repeatedly disrupted the Democratic-led House Judiciary Committee as it plowed through damning facts of Trump's conduct.

"They can't get over the fact that Donald Trump is the President of the United States and they don't have a candidate that they think can beat him. It's all political," said Collins, the panel's top Republican.

Republicans spent most of the day ignoring the Democratic mound of evidence that Trump abused his power by asking Ukraine to investigate a political rival -- Joe Biden.

They instead tried to establish the obvious fact that Ukraine was a corrupt country -- and that Trump was therefore justified in withholding $400 million in military aid and an Oval Office visit from the Ukrainian President.

At one point, Republican counsel Steve Castor tried to argue that the impeachment charges were moot since Biden -- the nationwide Democratic frontrunner-- wasn't a true rival for Trump.

"I wouldn't agree with that ... it's too early," Castor said.

Trump's almost mystical capacity to enlist Republican supporters was also at work on Sunday when his former bitter rival went on NBC's "Meet the Press" to defend the President.

Cruz, a Russia hawk, insisted that Ukraine interfered in the 2016 election -- thereby offering Trump a rationale for seeking investigations from Zelensky.

"Here's the game the media is playing. Because Russia interfered, the media pretends nobody else did. Ukraine blatantly interfered in our election," Cruz said.

The Texas senator however was basing his comparison largely on newspaper columns by Ukrainian officials and public criticisms of Trump. Such "meddling" falls far short of the sophisticated intelligence, computer hacking and misinformation campaign mounted by Russia to help win Trump election -- as described by former special counsel Robert Mueller in his report. (CNN)

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