House Ways and Means Chairman Richard Neal is prepared to issue a subpoena for President Donald Trump’s tax returns if the administration refuses to turn them over, an aide said Thursday. In a letter to IRS Commissioner Chuck Rettig on Wednesday, Neal (D-Mass.) demanded that by next week Rettig hand over six years’ worth of Trump’s personal tax returns and those of some of his businesses. But Trump left little doubt that he would resist the effort, repeating claims that he is being audited by the IRS. The fight could escalate into a court battle, but Neal wouldn’t discuss that...