For the first time since 9/11, passengers will soon be able to carry small knives, golf clubs, even hockey sticks on planes. The change, intended to conform with international rules, takes effect April 25. There will still be some restrictions. Knives can't be longer than two inches. And if you're carrying golf clubs, you can only have two. TSA officials stress the importance of risk-based screening, to focus on the biggest threats to aircraft rather than holding everyone to the same security standard.