While Houston drowns and North Korea provokes, the case for the impeachment of President Trump is growing stronger. The news of Hurricane Harvey’s destruction and Kim Jong Un’s latest missile test has obscured a series of unrebutted revelations that strengthen the already sturdy case that the president has obstructed the FBI investigation into the ties between his campaign and the Russian government.

The revelations shed new light on both the chummy ties between the Trump campaign and the Russian government and on Trump’s recent efforts to hinder the investigation of special prosecutor Robert Mueller.

Not only did Trump’s business associates appeal to Russian officials in late 2015 and early 2016 for help in building a Trump Tower in Moscow, but Trump also personally called Sen. Thom Tillis (R-NC) in early August to denounce his legislation to protect Mueller from being fired.

In a July 20 interview with the New York Times, Trump said any investigation of his family business in connection with the Russia investigation would be a “violation” of Mueller’s responsibilities and grounds for his dismissal. Mueller, it is now clear, has called Trump’s bluff. He is delving deeply into Trump’s real estate dealings and how they relate to Russia’s efforts to influence the 2016 election.

So are congressional investigators. The Times reported Monday that the Trump Organization turned over emails related to the proposed Trump Tower deal to the House Intelligence Committee, which is also investigating Russian meddling in the presidential election.

'Someone who knows how to deal'

The Post reported that Michael Cohen, one of Trump’s closest business advisers, asked longtime Putin lieutenant Dmitry Peskov for help in “the development of a Trump Tower-Moscow project in Moscow City.”

“As this project is too important, I am hereby requesting your assistance," Cohen wrote. "I respectfully request someone, preferably you, contact me so that I might discuss the specifics as well as arranging meetings with the appropriate individuals.“

Cohen’s email, the Post noted, "marks the most direct outreach documented by a top Trump aide to a similarly senior member of Putin’s government." The deal never came to fruition.

Cohen said in a statement to Congress that he wrote the email at the recommendation of Felix Sater, a Russian American businessman who was serving as a broker on the deal. The Times reported that Sater had boasted the deal could help elect Trump, which may have been the sort of hype that routinely lubricates real estate deals.

But Sater’s email to Cohen, published by the Times, voiced hope for a relationship that would go beyond real estate.

“Michael we can own this story," Sater wrote. "Donald doesn’t stare down, he negotiates and understands the economic issues and Putin only want to deal with a pragmatic leader, and a successful businessman is a good candidate for someone who knows how to negotiate. ‘Business, politics, whatever it all is the same for someone who knows how to deal’…"

Mueller's strategy

The question of how Trump sought to deal with Russia is at the heart of Mueller’s investigation.

The proposal for a Trump Tower in Moscow was just another manifestation of Trump’s long-standing desire to build in Russia. In 2013, he signed a preliminary agreement to build a hotel in Russia in partnership with Aras Agalarov, a billionaire who had financed the Trump-owned Miss Universe pageant in 2013.

A representative of Agalarov’s company attended a June 2016 meeting with top Trump aides and a Russian lawyer organized by Donald Trump Jr. The lawyer offered to provide damaging information about Hillary Clinton collected by the Russian government. The meeting was “part of Russia and its government’s support for Mr. Trump,” according to an email made public by Don Jr.

Six days later, a person identifying himself as "Guccifer 2.0" released a Democratic National Committee file on Trump, stolen from the DNC computers. It was the first in a flood of leaks harmful to Clinton that would continue for the rest of the campaign.

According to an NBC News report Monday, Mueller’s team of prosecutors are focusing on Trump’s role in drafting a public statement claiming the subject of the meeting was the adoption of Russian orphans by Americans.

A source “familiar with Mueller's strategy” told NBC that whether or not Trump made a "knowingly false statement" is now of interest to prosecutors.

"Even if Trump is not charged with a crime as a result of the statement, it could be useful to Mueller's team to show Trump's conduct to a jury that may be considering other charges.”

The revelations show the president and the independent counsel are on a collision course that can only end in a constitutional crisis and impeachment proceedings.

The threat to bring Trump's conduct to a jury is a threat to Trump’s family and his presidency. Trump’s pardon of Arizona sheriff Joe Arpaio, convicted of contempt of court for disobeying a court order to cease the profiling of Latinos, shows he believes his political whims take precedence over the workings of the law.

Trump has spoken privately about firing Mueller, only to be talked out of it by aides. Senate Minority Leader Chuck Schumer has said Mueller’s dismissal would be a "tipping point" for Senate Republicans. Sen. Lindsey Graham has said firing Mueller would be "the beginning of the end" of the Trump presidency.

The tipping point is drawing closer.