I think if the House had subpoenaed Bolton, he would have refused to show up. This would have opened him up to be sued, but it would have been a long, drawn ou

I think if the House had subpoenaed Bolton, he would have refused to show up. This would have opened him up to be sued, but it would have been a long, drawn out process in the courts, which would have prolonged the impeachment proceedings by several months, by which time public opinion on the impeachment proceedings could have become negative.