For the first time in the United States, two high-speed rail lines are being built in California and Nevada, while others are planned in Texas, Georgia, North Carolina, Oregon and Washington. As early as 2028, passengers may be able to travel between Las Vegas and Southern California at speeds of up to 200 mph. Although such high-speed trains are common in Europe, China and Japan, high costs and contentious political battles have slowed the technology in the United States.

But times could be changing, say executives and advocates of high-speed rail projects. They believe the United States could be on the cusp of a new high-tech manufacturing industry for these trains and the infrastructure they need, which could create jobs and give travelers a safer, more sustainable alternative congested roads and the hassle of flying.

For this three-part series, Smart Cities Dive took a close look at the history of high-speed rail stops and starts in the United States and spoke with key industry and government players about what the future might hold for us. Here are the challenges and opportunities they see.