Elon Musk is closely bound up in another election. His involvement in European politics is only deepening.

Elon Musk, the CEO of Tesla and SpaceX and a close advisor to President-elect Donald Trump.

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• Elon Musk used his fortune and influence to help Donald Trump win reelection in November.
• The Tesla and SpaceX boss is now championing right-wing insurgent politicians in Europe.
• Musk has endorsed Reform UK in Britain and hailed Germany's far-right AfD as the country's savior.

Having tapped his vast personal wealth and marshaled his 210...