International aviation security efforts have been in place and imperative since the 911 attacks. According to U.S. Department of Homeland Security Secretary Janet Napolitano, each airport in the United States conducts its different checks randomly, and "deliberate uncertainty is built into the system." What is not uncertain or ambiguous are the baggage rules, which are quite definitive as of 2010.
You are allowed to take through the security checkpoint as many 3.4-oz. containers of liquids or gels that will fit into a quart-size, clear plastic zip-top bag. (If you need to take more shampoo, for example, either prepare another 3.4-oz container or pack a larger bottle in your baggage and check it.) You are not allowed to carry on your snow globe or walk on your gel insoles. Put them in your baggage and check them. Medications, milk or juice for babies, or any other liquid necessities in excess of 3.4 oz. must be declared at the checkpoint. (You don't have to put these items in a zip-lock bag.) If you want to bring something for yourself to drink on board, you must buy it from one of the vendors after the checkpoint.
Anyone who has been hit by a hockey stick or a golf club knows what weapons they can be. Bows and arrows, bats, spear guns, ski poles and even pool cues cannot be carried onboard an airplane, although all of these items may be checked in baggage. You may, however, carry on your fishing pole if it fits into an overhead compartment. Sharp tackle equipment must be checked, but if you have fragile items, you may slip them into your carry-on bag. Check your paintball gun, but not the CO2 system.
For obvious reasons, guns, firearms and ammunition cannot be carried onboard an airplane. If you want to pack them in baggage that you will check, you must declare unloaded firearms at the ticket counter in a locked case or container. If the security officer needs to open the container you must remain with him until the case is re-locked.
Heavy tools can also be construed as weapons, so you will have to check your hammers, drills, saws, hatchets and axes as long as they are properly wrapped so that no blades could cause injury to a luggage handler. Screwdrivers and wrenches may be tucked into your carry-on bag if they are less than 7 inches in length.
No martial arts items are allowed to be carried onto the aircraft. That means your nunchakus, night sticks, brass knuckles and throwing stars have to be safely packed away in your luggage to be checked.
Other than lighters without fuel, no flammable or explosive materials are allowed on the aircraft. Period.
Manicure scissors and safety razors can now be packed in a carry-on bag. But there is still no provision for carrying box cutters, ice picks, knives, meat cleavers, razors and swords. These items, however, may be included in checked baggage if they are properly sheathed and/or wrapped so that there will be no danger of handlers getting cut by a protruding blade.
