After the arrival of a less costly A.I. model from China, U.S. markets and academics are wrestling with the ultimate economic value of the technology.

The electric car company run by Elon Musk is facing increasing competition, but investors have focused mostly on the prospects for Tesla’s self-driving technology.

Automakers and even some Republicans may fight to preserve funds, and environmental activists will likely sue, but some experts said that some changes may not survive legal challenges.

Rules for a $7,500 tax break for electric vehicle purchases and leases recently changed, but more far-reaching changes are expected when President-elect Donald J. Trump takes office.

More car buyers are expected to eventually pick battery-powered cars and trucks as prices fall and technology improves, even if Biden-era incentives disappear.

Mr. Musk has fallen out with prominent right-wing Americans who say they are worried that their agenda may be sidelined in favor of his own — and that he is willing to silence them on X.

Fellow soldiers say the Army sergeant who set off the explosion could have done far more harm. Investigators are trying to figure out why he didn’t.

The two episodes have superficial similarities, including that both suspects used the same car rental app.

Officials said they used data from Tesla charging stations to chart the driver’s dayslong journey from Colorado to the Trump Hotel in Las Vegas.

The F.B.I. says no connection has been found between the truck explosion outside a Trump Hotel and the truck attack that killed 14 people in New Orleans.

The electric-car company led by Elon Musk no longer has the market to itself. Investors are focusing on autonomous driving and other new technologies.

Sales of the company’s cars are flagging, but investors are focusing on the potential of autonomous driving and Mr. Musk’s ties to President-elect Donald J. Trump.