President Donald Trump and Democratic challenger Joe Biden would likely steer automotive policy in different directions over the next four years, potentially changing the industry's road map to the future.

Why it matters: The auto industry is on the cusp of historic technological changes and the next president — as well as the next Congress — could have an extraordinary influence on how the future of transportation plays out.

What to watch: Three big policy issues — infrastructure, vehicle emissions and self-driving car technology — will influence the industry's direction in the coming years, making the candidates' positions on each critically important.

Infrastructure: Both candidates promote big infrastructure spending to rebuild roads and bridges; expand 5G and rural broadband, and create jobs.

• President Trump has been touting a $2 trillion infrastructure plan throughout his presidency but it hasn't progressed, mostly because of disagreements about how to fund it.
• Biden's $1.3 trillion infrastructure proposal is tilted toward his clean energy agenda and would include strengthening the electrical grid and building 500,000 electric vehicle charging stations by 2030.
• No matter who wins, the next president will have to work with Congress on a long-term fix for the nearly insolvent Highway Trust Fund, potentially raising the federal gas tax or creating a new usage tax based on vehicle miles traveled.

Emissions and fuel economy: This is where the biggest policy differences exist between the candidates.

• The anti-regulatory Trump rewrote vehicle emissions standards through 2026 to make them "more achievable" than the strict targets set by the Obama administration (though he did endorse zero-emission EVs during a recent debate).
• Trump also revoked California's Clean Air Act waiver that allowed the state to regulate its own tailpipe emissions, prompting a federal court challenge.
• Biden's plan includes a huge commitment to electric vehicles, expanding consumer incentives and filling government fleets with EVs.
• If Biden is elected, he'd likely restore the California waiver and abandon the legal fight, which could help reunite automakers caught in the crossfire.
• The next administration will also have to take up fuel economy and emissions rules for beyond 2026, with Biden likely to set far more aggressive targets than Trump.

Autonomous vehicles: It's not clear how either candidate feels about self-driving cars, although Axios reported last year that Trump thinks they're "crazy."

• Under his administration, the Department of Transportation has taken a hands-off approach to AV regulation, providing voluntary guidance to AV tech companies but leaving it up to states to set their own rules for testing and deployment.
• However, the DOT is weighing a rule that would lift regulatory barriers for cars without a steering wheel and pedals.
• Biden hasn't addressed whether there should be a federal AV policy.
• It's on Congress' agenda, though — House lawmakers told Automotive News they'll renew efforts to pass an AV bill starting in January, regardless of who is elected president.

Yes, but: The most important policy that could help the auto industry — and the overall economy — are those that get the coronavirus pandemic under control.