Today the Northstar Commuter Rail line opens from Target Field to Big Lake, with an extension to St. Cloud coming soon. It’s a commuter rail line, meaning that it’s a full-blown train operating on existing tracks, costing $320M for the 40 miles that it will run. It’s expected to carry about 4,000 people per day in a few years at speeds up to 80 MPH, but experts say that ridership may be much higher. As the hoopla becomes a staple on the news for the next few days, a lot of us in Saint Paul might be wondering when we get our ride – and the answer is that we could have had something just like this by now. But we don’t.