Business news today is being driven by President Trump’s assertive use of executive power, with implications from trade to national security to energy markets. He signed a new order imposing 50% tariffs on many Canadian goods, escalating a dispute over autos, alcohol and dairy and threatening to deepen strains in one of America’s most important trading relationships. At the same time, Trump said the Qatar-donated Boeing 747 being adapted as Air Force One will be pulled back for another round of security upgrades, underscoring concerns about whether the aircraft is sufficiently hardened for presidential travel. Global markets are also on edge: Brent crude climbed above $90 a barrel as fresh U.S.-Iran strikes and mounting risks around the Strait of Hormuz raised fears over oil flows. In contrast to the geopolitical turbulence, Jersey Mike’s is pressing ahead with a blockbuster IPO that could value the sandwich chain at nearly $8 billion.