Here's why Trump is going to have a hard time defending himself against obstruction of justice now

The recent disclosure of the email exchange between Donald Trump Jr. and publicist Rob Goldstone may be the key to the obstruction of justice investigation into the president.

According to a report from Just Security by Harvard law professor Alex Whiting, the investigations into the Trumps and Russia have been approaching the case from two different perspectives. One is about the Russian hacking of the 2016 election and the Trump family's knowledge of it. The second is about whether President Donald Trump obstructed justice when he fired former FBI Director James Comey. While the two have always been related, Trump Jr.'s email brought the two crashing together.

While the media is focused on the stories surrounding Trump Jr. (collusion), the story also supports the other investigation into obstruction. The charge is that the elder Trump sought to kill the FBI's investigation into former National Security Advisor Michael Flynn and the possible collusion between Russia and the Trump campaign. While Trump's conversations with Comey aren't disputed the question of his intent has been. The question is whether he acted "corruptly" with the intent and purpose of firing Comey in order to stop the investigation.

The allegations were initially flat given the Trump administration's defense that there was no intent of wrongdoing by the Trump campaign and Russian hacking, Whiting explains in the report. As a result, it will be more difficult to prove if there were no blunders to hide.

He wonders if a prosecutor could convince a jury that in Trump's own bumbling way he was trying to put in a good word for Flynn. Conversely, a prosecutor could also convince a jury that firing Comey was about Trump's own conclusion that the Russia investigation was being badly handled and he needed a more capable Director. Whiting argues whether a jury or Congress -- they might be more like to give Trump the benefit of the doubt.

However, the new information could make the case that Trump's own son and son-in-law were involved and Trump wanted to protect his family by firing the head of the FBI. Whiting argues the sudden firing of Comey and his flood of tweets and public statements on Russia makes his actions appear far more sinister. Trump could have something to hide after all.

He cites Bob Bauer, who explained how the Trump campaign could be considered criminal, and even if the evidence doesn't reach the level of criminality, it still severely damages the president, his administration and those close to him.

Recall Trump's obsession with the size of his crowd at the inauguration and the size of his electoral win -- he's notorious for trying to give evidence of his credibility. Reports show the White House has been in absolute chaos while Trump "rages" at the media for the reports. Whitting argues the recent revelations have a real possibility of slowing the work of the White House to a crawl before they ever really even get started.

"When Trump engaged in his alleged acts of obstruction, did he have a sense that the investigation would ultimately unravel this story that is now emerging?" Whitting asks. "With regard to Flynn, did he know that Flynn’s story was an important piece in the larger picture, one that he did not want revealed? Or did he know that the FBI’s pressure on Flynn could force him to give up other incriminating evidence? Far from simply acting to shield a former subordinate and ally, was Trump actually just trying to protect himself, and those close to him?"

If any question is answered with "yes," Trump's defense or plea of ignorance gets a lot less believable.