What impeachable offense? Seriously?!
Not only his foreign business ties, the ramifications of which are bad enough with respect to foreign policy and protecting American interests vs his personal business interests. It is also a fact, as reported by all intelligence agencies in the nation (CIA, FBI, etc), that Russia not only hacked into RNC and DNC servers with the intent to corrupt our electoral process, but they did so expressly to support Trump against Clinton. This has been proven to be a fact thus far.
The question now is, did Trump and/or members of his campaign traitorously collude with Russia in this anti-democratic scheme? The whole point of the multiple investigations being carried out into Trump and his team, including the FBI's investigation which had been led by former director James Comey, is to reveal the answer to this question.
Trump then decided to fire Comey. After VP Pence and Press Sec. Sean Spicer publicly declare that it was Deputy Attorney General Rubenstein's recommendation to fire Comey and that Trump simply went along with it, Trump himself counters them by announcing on live TV during an interview that he fired Comey entirely on his own volition, and expressly did so because of the Russian investigation! It was then revealed that Trump had asked Comey to be loyal to him during a dinner just prior to the firing, to which Comey apparently gave an unsatisfactory answer in Trump's eyes by saying he'd be honest.
How is it not suspicious that someone being investigated by the FBI not only fires the FBI director, but also admits he did so because of the investigation? That he had the gall to meet and dine with the FBI director investigating him (which itself is suspicious) to encourage him to be loyal, firing him after being told he'd be honest instead?
Honestly... I am astounded at how many Americans continue to fail to grasp the situation and its gravity.
Trump also expressly and publicly encouraged Russia to do what it did in one of his campaign rallies last year, which is to say he traitorously encouraged Russia to corrupt our electoral process. And at this point, one of Trump's former cabinet members, Michael Flynn, has been caught lying about his foreign ties. Flynn's asked for an immunity deal, so he doesn't incriminate himself with what he has to say about the Trump campaign and Russia. Press Secretary Sean Spicer lied when he attempted to deflect the blame for Flynn onto the Obama administration, claiming Obama should have vetted Flynn properly. In reality, Spicer omitted the facts that there are different levels of security clearance, that Obama kept Flynn in check with minimal clearance as suspicions began to mount, and even warned Trump about his rising concerns about Flynn. Trump then promoted and granted Flynn the highest security clearance he would enjoy. Trump's former campaign manager as well has been tied to Russia in an incriminating manner, bringing us to two highly suspicious Trump campaign members caught in their lies, and Trump's own actions and words have been apparently incriminating.
With an independent special counsel on the case now, we will see how this unfolds. Lets just say I won't be surprised if Trump fires Rubenstein in order to get a new Deputy Attorney General willing to put an end to the investigation... which is what President Nixon did over 40 years ago when Watergate was being investigated.