(CNN) Donald Trump has been president for 577 days as of today. One year and seven months, to the day, of what can be described without exaggeration as the least predictable presidency in modern history. And yet, for all the wackiness and whip-sawing of these first 19 months, there's a very credible case to make that the next two-ish weeks are the most critical of Trump's presidency to date -- and will set a course for the remaining years of his presidency that will be very difficult to alter.

Consider:

1) The jury in former Trump campaign chairman Paul Manafort's trial on a series of alleged financial crimes entered its third day of deliberation on Monday. While the case focuses on Manafort's interactions with the Ukrainian government prior to his time at the head of Trump's campaign in 2016, it grew out of the special counsel probe into Russian interference in the 2016 election being led by former FBI chief Robert Mueller. A Manafort conviction would provide momentum for the special counsel's office in advance of the release of Mueller's report on his investigation. (Much more on that below.) If Manafort gets off -- and, to be clear, he will still have to be tried in Washington, DC, on similar charges -- it will give Trump's "witch hunt" attacks more fuel. "See, I told you all along this was a hoax," Trump will tweet -- again and again.

3) We appear to be in the final stages of protracted negotiations between Trump's legal team and the special counsel's office about whether Trump will sit down with Mueller and answer questions. On "Meet the Press" on Sunday, Trump lawyer Rudy Giuliani said that Mueller's investigators "have taken 2-3 weeks to get back to us, so what I have to tell you is, look, I am not going to be rushed into having him testify so that he gets trapped into perjury." The special counsel's office has been tight-lipped about, well, everything -- including whether or not Trump might sit down with Mueller's team. But given Giuliani's repeated assertions that the two sides are entering the latter stages of the negotiating process, it's hard to believe we won't have a decision in the relatively near future.