Patdowns are just part of our lives these days. Bring the family to most tourist spots around town, and prepare for the searches and the metal detectors and the rules. Then try the National Geographic Society building, which houses a museum with frequent family-friendly exhibits. Here you’ll find a sane security presence. The guards will see you but won’t hassle you. If you have a stroller, you can just park it off to the side without triggering a lecture. Enjoy the exhibits and the gift shop and whatnot without cursing the post-Sept. 11 security complex.