1) Trump tells Turkey's Erdogan its cool to attack Kurds in northern Syria
2) Turkey kills/displaces Kurds
3) Kurds reluctantly cut deal with Russia/Syria to help them
4) US military caught in middle evacuates (blowing up its own bases)
6) Within hours Turkey continues offensive, mocking Trump's letters and agreements.
Turkey got the buffer into Syria they always wanted with no repercussions, even praise, for "cleansing" Kurdish lands. Unmitigated victory for Turkey.
ISIS stoked to be free to grow again.
Final player: while this is unmitigated disaster for US and President Trump, was there something in it for Trump Family that made it worth it for him to sell-US-out?!?