Shares of defense prime contractor Lockheed Martin have been under siege amid changes in U.S. leadership and questions about the viability of technologies it produces.Now, Canada is questioning its purchase of Lockheed’s F-35 jet fighters,

Portugal said it was reconsidering purchasing the Lockheed Martin-made F-35 jet in the wake of Trump's recent policy shifts.

Questions are mounting in Canada and in Europe over whether big-ticket purchases of high-end U.S. weaponry, such as the F-35 Joint Strike Fighter, are still a wise strategic choice for Western countries worried about their investment in U.