I wish I knew. General Flynn was kneecapped by not only Clapper, Brennan, and Comey, but also by the Pentagon. It was DOD’s Office of Net Assessment that was paying Halper to set up Flynn as some sort of Russian asset, the product of an alleged romantic liaison with a Russian Brit who is now suing Halper for damaging her reputation. These people are vicious who will do anything to take down people who don’t go along with the program. Even the former head of DIA is fair game.
From Wikipedia, on Flynn's end of his military career:
According to what Flynn had stated in one final interview as DIA director, he felt like a lone voice in thinking that the United States was less safe from the threat of Islamic terrorism in 2014 than it was prior to the 9/11 attacks; he went on to believe that he was pressed into retirement for questioning the Obama administration's public narrative that Al Qaeda was close to defeat.[41] Journalist Seymour Hersh wrote that "Flynn confirmed [to Hersh] that his agency had sent a constant stream of classified warnings ... about the dire consequences of toppling [Syrian President] Assad."
Flynn recounted that his agency was producing intelligence reports indicating that radical Islamists were the main force in the Syrian insurgency and "that Turkey was looking the other way when it came to the growth of the Islamic State inside Syria". According to Flynn, these reports "got enormous pushback from the Obama administration," who he felt "did not want to hear the truth". According to former DIA official W. Patrick Lang: "Flynn incurred the wrath of the White House by insisting on telling the truth about Syria ... they shoved him out. He wouldn't shut up."
In an interview with Al Jazeera, Flynn criticized the Obama administration for its delay in supporting the opposition in Syria, thereby allowing for the growth of Al-Nusra and other extremist forces: "when you don't get in and help somebody, they're gonna find other means to achieve their goals" and that "we should have done more earlier on in this effort, you know, than we did."
On April 30, 2014, Flynn announced his retirement effective later that year, about a year earlier than he had been scheduled to leave his position. He was reportedly effectively forced out of the DIA after clashing with superiors over his allegedly chaotic management style and vision for the agency.
True enough.
And I have no doubt that Gen Flynn, better than anyone, knows exactly where those "battle lines" are drawn.