(CNN)The Congressional Budget Office has predicted the federal deficit could reach $1 trillion by the 2020 fiscal year. Once again, President Trump has exposed a myth in American politics. That myth? That Republicans are the party of fiscal responsibility. He is just the latest Republican president to demonstrate this. His drive for corporate tax cuts, which received strong Republican support, has blown a huge hole in the federal ledger. Tea Party Republicans once railed against President Barack Obama's spending habits. As the deficit has grown under Trump, however, they've suddenly changed their tune. Acting Chief of Staff and Office of...