If you are traveling by air and plan on checking bags the TSA (who are responsible for airport security) xray each bag that is to be a carry on and require it to be unlocked. This is a recent rule in affect in the airports I have been through lately.

As such I'd take any necessary precautions about what is sent through carry-on and what is sent as baggage.

I have been able to stay with my baggage through the Xray procedure - this is performed at the check-in point - and reseal my bag afterwards, but can't guarantee that this is always possible.

There is a CNN article hyperlinked below with some tips that might be useful.