Japanese carmakers are in dire straits, with Toyota likely to be the worst hit due to their huge U.S. exposure, according to Vivek Vaidya, global client leader for mobility at research firm Frost & Sullivan.

Walking through a Michigan plant past whirring robotic arms and flying sparks, Swamy Kotagiri, the CEO of Canada-based auto supplier Magna reflected on how he is trying to "control the uncontrollable" in the midst of industry-shaking tariffs.

The major car companies say sales rose sharply in March, with most reporting double-digit gains. For some companies, the strong performance last month helped make up for a sluggish start to the year.