TORONTO - Toronto airport is almost back to normal after new security restrictions caused near chaos for days for travellers heading to the U.S. But there are now questions being raised on whether the restrictions will be made permanent. David Jacobson, the U.S. ambassador to Canada, flew into Pearson yesterday and says American officials are re-evaluating procedures and he will wait to see what they decide. He says the focus in the U.S. is to try and balance security on one hand with efficient travel and commerce on the other. Heightened security and new restrictions on carry-on luggage were ordered after a Nigerian man allegedly tried to bring down a Northwest Airlines flight from Amsterdam to Detroit. Transport Canada says no decisions have been made about when -- or if -- the new rules will be lifted.