California's high-speed rail project was billed as the future of transportation, but with President Trump moving to pull $4 billion in federal funds, its future remains precarious. Why it matters: The system was initially slated for completion in 2020.

A federal probe by the Trump Administration determined the California High Speed Rail Authority in default on terms of two federal grant awards.

The Trump administration said it would pull roughly $4 billion in federal funding for California’s long-planned high-speed train, a project that has, over decades, become an avatar for the country’s declining ability to complete transformative new infrastructure.