At another level, the breakup was a reminder of something else: the perils of personality-driven investing, a growing and lucrative business for the Wall Street bankers cranking out, rapid-fire, a never-ending array of new financial products.

As Trump's sweeping tax-cut and spending bill marches forward, analysts examine how his broad-ranging policies could turn the fortunes of US companies.

Wall Street's stock indexes ended lower on Thursday in choppy trade as a slump in Tesla shares offset news of progress in tariff talks between U.S. President Donald Trump and Chinese leader Xi Jinping.