A timeline of the praises and insults that President Trump and Elon Musk have lobbed at each other shows how their volatile clash was years in the making.

Elon Musk, initially a strong supporter and advisor to President Trump, is being an outspoken critic of Trump's legislation. He briefly led the Department of Government Efficiency (DOGE).

The two have been trading barbs on social media since last week, with Musk calling Trump’s sweeping tax and spending proposal ...