After Rep Ryan announced he was out of the running in Nov's election....I sat and paused over the likely reasons here.
1. I think Ryan anticipates that a Democratic win will occur this fall, with slight edge to the Democrats in the House. The Senate will remain at 52 to 54 GOP members.
2. I think Ryan anticipates that the Democratic House will draw up impeachment papers. The question will be if five or more GOP Senators cross the line and accept on the charges.
3. I think Ryan anticipates an impeachment process for 2019, and he likely jumps into the Presidential primary by the end of 2019.
Maybe I'm wrong.