San Francisco - Huge and possibly unprecedented numbers of people tuned in on Tuesday to hear appeals court arguments over President Donald Trump's travel ban.The San Francisco-based 9th Circuit Court of Appeals live-streamed the audio arguments between lawyers for the state of Washington and from Trump's Department of Justice over the suspension of the nation's refugee programme and immigration from seven mostly Muslim countries.On YouTube alone over 136 000 people listened to the live-stream at its peak. But the audio was also streamed on the Facebook and web pages of news outlets, and carried at least in part on CNN and MSNBC. Immediate figures for all those sources are not available, but they likely took the number of listeners well past a million.Those figures are staggering for the type of procedural arguments that would normally attract only a tiny handful of assigned reporters and other professional observers.The 9th Circuit has made a practice of providing audio live-streams of its hearings but it's a recent innovation, and one rare for a court so high in the appeals process. The US Supreme Court only provides recordings of its hearings, usually well after they're over.Tuesday's audio combined with the intense public interest and politic engagement of the early Trump administration made the hearing a genuine event, with both amateurs and professionals live-tweeting and commenting as it was happening. It felt for some listeners both modern and old-fashioned."Americans are listening to a court hearing the way my grandpa listened to Cardinals games in the 50s," Mike Tibbetts of New York said via Twitter during the arguments. "This is progress."