By Mike Dolan

LONDON (Reuters) - What matters in U.S. and global markets today

By Mike Dolan, Editor-At-Large, Financial Industry and Financial Markets

World markets and the U.S. dollar have surged this morning after a shock U.S. court ruling overnight that said the bulk of President Donald Trump's sweeping import tariff hikes were outside his authority.

I'll discuss the implications of this below along with the rest of the morning's market news before getting into today's deep dive, where I explain why Germany may not remain long in its new role as the world's top creditor.

Today's Market Minute

* A U.S. trade court blocked most of President Donald Trump's tariffs in a sweeping ruling on Wednesday that found the president overstepped his authority by imposing across-the-board duties on imports from U.S. trading partners.

* Billionaire Tesla CEO Elon Musk is leaving the Trump administration after leading a tumultuous efficiency drive, during which he upended several federal agencies but ultimately failed to deliver the generational savings he had sought.

* NATO will ask Germany to provide seven more brigades, or some 40,000 troops, for the alliance's defence under new targets for weapons and troop numbers that its members' defence ministers are set to agree on next week.

* In the faceoff between heavily indebted developed economies and increasingly wary investors, Japan has blinked first, announcing that it will reconsider its debt profile strategy. The U.S. could soon follow. Read the latest from Reuters columnist Jamie McGeever.

* The U.S. power system is on track to produce more electricity from clean power sources than from fossil fuels for the third straight month in May, a record-long stretch. Find out more in the latest piece from Reuters columnist Gavin Maguire.

Trump tariffs thwarted

The Manhattan-based Court of International Trade ruled on Wednesday that the U.S. Constitution gives Congress exclusive authority to regulate commerce with other countries, and that this authority is not overridden by the president's emergency powers.

In response, the White House quickly set an appeal process in motion, one that could go all the way to the Supreme Court.

But the trade court has, at least temporarily, invalidated all of Trump's orders on tariffs since January that were rooted in the International Emergency Economic Powers Act, a law meant to address "unusual and extraordinary" threats during a crisis.

While the ruling doesn't cover sector-specific tariffs on steel or autos, analysts said it does invalidate the 10% universal tariff, the global 'reciprocal' tariffs, levies on Canada and Mexico and the new China levies.