Devil is Dill
Doubleplusgood
I don't think it proves he was lying all along. It proves that he has alzheimer's or dementia. He can't remember what he said 10 minutes ago, yet alone on the campaign trail. He is constantly saying, tweeting or doing things that completely contradict things he has previously said, tweeted or done.
I think he just says whatever he thinks the people he's talking to at the time want to hear. He just wants approval - that's why he was acting like a middle schooler trying to impress the high school kids with the Russians last week.