can US citizens be charged with breaking US laws when they are in foreign countries?

Technically, no... US jurisdiction ends at it's international boundry.

In any case, there are several countries (US and Canada included) that have passed laws - primarily having to do with Sex Tourism & Child Prostitution - that would allow them to prosecute citizens once they return to the country for the appropriate sex crimes.

Whether these laws can stand a challenge in Federal Court is a matter of conjecture, as I don't believe they have been challenged...yet.

EDIT:

Foreign (military) bases are considered to be that country's soil, same as with an embassy.

A US citizen going to Cuba can not be charged in the US. Thousands of sun seeking US tourists go every year, but they have to fly into Mexico, Canada, Jamacia, etc; change planes, and then fly to Cuba...then retrace their steps to return to the US. (US anti-Cuban laws generally deal with companies or citizens entering into a *business* relationship with Cuba.)

It depends on the law in question, but the answer is a definite "sometimes".

One example that applies to everyone is the US Tax Code. It's laws apply to every US Citizen, regardless of where in the world they are. There are some differences in what parts apply, but the law does apply.

If a person is on Probation and one of the terms is that they cannot take a particular drug, associate with a particular person, or own a firearm, it doesn't matter where they are in the world, even if with their PO's permission. The activity is still a violation.

Not exactly what you asked, but there are also licenses and privileges issued by a US jurisdiction, including licenses to drive or practice a profession, and the conditions sometimes include that if a person commits a violation of the local country's laws, that may be a violation of the law pertaining to the license.

There is a law that makes it illegal to bribe an individual in a foreign country. Some US citizens have been charged under this law for bribery activities of their companies foreign subsidiaries. Foreign Corrupt Practices Act

It depends on the status of the American citizen. Definitely in the case of Military or diplomatic corp, the laws of the US still apply despite being in a foreign country. For regular tourists, the laws do not generally apply unless the activity carries over to the US. For example, a 20 year old can get drunk in Mexico and be fine, but get in trouble if they are still intoxicated when they cross the border back to the US.

The short answer is yes.

It depends on the actual law, but some are designed to holdup outside the US territory.

For example, Conspiracy law, Terrorism laws, Trade Embargo, Technology divulgence laws are all enforceable on US citizens outside the US.

But basically, it has to be an infraction against the US.

If you go to a foreign country, and drive while your US license is revoked, you won’t suffer punishment from the US.

It all depends on which laws were broken. Pedophilia for instance, you can go to a country where the laws are not enforced or certain ages are legal that aren't legal in the U.S., participate in the activity and not be charged, BUT when you get back to the U.S. you would be charged with breaking the U.S. law that pertains to child sexual abuse/molestation or whatever is appropriate. And to the legal system's credit, this is as it should be.

I'm sure there are other laws that are equally enforceable once you get back to the U.S.

Yes, most assuredly yes. If you bribe a foreign official, you can go to jail in the US. Just one example. If you break a foreign law, that is not illegal in the US you fcan be prosecuted, an example - it is illegal to use the swastika in Germany. Even model planes can't use swastika decals. in the US, you can be prosecuted.

almost certainly not.

it would take some unique circumstances for you to be arrested for violating US laws if you weren't in the US.

Like - if you are in another country, but on the grounds of a US Embassy, the US laws are in force.

I have no idea about whether a US military base or post in considered US territory.

and if you were part of a conspiracy with someone in the US ?

possibly. but it would be rare.

Good question...the answer is no. If you are in a foreign country the only laws you have to worry about are the laws of that country.

no. you can be charged only by the book of the court, which is the law of the country you are in