The Globe and Mail reports in its Saturday edition that the U.S. Supreme Court ruling against Donald Trump's suite of tariffs is not only a setback for President Donald Trump's trade policy. Guest columnist David Shribman writes that the ruling also delivered a substantial defeat to the principal philosophy of the Trump administration, which holds that the presidency has inherent powers that the Constitution does not specifically provide. The court has said that there is no authority for the President to impose tariffs on a whim. It is the first time the court has struck down a major Trump initiative in his second term and suggests it may also strike down his effort to ban birthright citizenship. The ruling also represents a sharp rebuke to the Trump administration's view of nearly unrestricted executive powers and it has the ancillary effect of affirming the independence of Congress. Friday's high court decision does not mean that tariffs will no longer be a part of U.S. economic policy . American presidents have many other statutes that can be invoked to impose tariffs, but it is now more laborious to do so. Mr. Trump has now signed an executive order imposing a global 10-per-cent duty for 150 days starting Feb. 24.