Remember, you don't have the protections that you do in the U.S.  You are subject to the laws of that country’s legal system. That probably does not allow for bail or the right to a speedy trial.
 

If arrested, ask immediately that the U.S. Embassy or Consulate be notified.  Ask as firmly as possible, to speak with the U.S. representative.

U.S. officials will help you to locate an attorney, provide basic advice and notify relatives and friends back home of your situation.

The Embassy or Consulate can only make requests on your behalf.  They don’t have the authority to intervene in the other country’s  criminal or legal matters.

When in port  your time can be your own or you can book a shore excursion.  Checking out a port on your own is great fun but it can also be a challenge.

A big ship full of tourists means all locals will be converging on the area to check out the potential shoppers and sightseers.  Being on the ship labels you as wealthy, whether you are or not.  You are compared to the people in most parts of the world.  An unknown port could be dangerous, so you’ll need to be careful.  Learn as much as possible about a specific port and the country before arriving.

Doing your homework could greatly enhance your safety.  Less experienced traveler should probably consider the cruise line’s shore excursions.  They may be more restricted than being on your own, but you might have more chances to enjoy the area since you’ll know you’re safe.  Shore excursions sold on board the ship can vary in cost.  Find out in advance what they are so you can compare with on local sightseeing offers or just wandering on your own.

travel.state.gov/ Try the U.S. State Department’s Travel Warning and Consular Information web page.  It contains detailed information on foreign countries’ entry requirements, safety, crime, medical facilities, traffic and aviation safety, customs, criminal penalties and special issue information.  It also furnishes contact information and web links to foreign Embassies and Consulate offices.

https://www.cia.gov/library/publications/the-world-factbook. This is the U.S. Central Intelligence Agency’s country listing section of the CIA’s World Factbook web page.  It contains detailed information on foreign countries.  This information is particularly useful to the business traveler.  It also includes information can be helpful to the tourist or vacationer.

Avoid narrow alleys and dimly lit streets.

Try to keep away from crowds of people whenever possible.

Keep a dummy wallet in a back pocket and carry cash in your front pocket.

Place a rubber band around a few loose credit cards and carry them in the other front pocket.  It's unlikely that someone could remove them without your knowledge.

Ladies, carry your purse firmly under your arm.  If it has a strap, put your arm through it.

As an alternative, carry your money under your clothes or in a "fanny pack" close to your body.

Be aware of the more common pickpocket's tricks

Crowds of people bring out pickpockets and allow them the cover needed to relieve you of your cash or credit cards.  Be particularly diligent in the following situations : 

Being bumped by someone, even when it's not crowded.

Having something spilled or sprayed on you.  Often someone will point out a spot on your clothing or a rip or tear.

A stranger approaching you for help or directions.

A sudden disturbance occuring, drawing everyone’s attention.

Watch out if you are surrounded by a small crowd or group of children.  Also, packs of 2 or 3 people often work subways and trains.  It's difficult to keep an eye on more than one. 

Do your homework in advance.  Find out what risks, if any, you may face.

If you've brought valuables with you, leave them in the ship’s safe or the cabin safe if it has one.

Avoid wearing flashy jewelry.   Don’t draw attention to yourself by displaying large amounts of cash.