I've never had an issue with vacations in the US [snip] When I go abroad (out of North America), I call up my credit card company, and tell them what countries I'm visiting, and give them the dates of travel

That's the secret!

When I was bringing the ShoWagon back from New Hampshire, my main credit card was suspended mid-trip because of quite truly fraudulent use -- a website with my credit card info had been hacked, and the criminal genius used my card to place long distance phone calls from his home phone.

So my emergency reserve almost never ever used backup card came into play -- and by the time I got out of Canada, that card also got suspended because (understandably) my credit card company became concerned that this card than hadn't been used for 5 years suddenly got used over a three day period in three states and two Canadian provinces.

Fortunately I had just enough cash in my wallet to buy the last tank of gas I needed for the rest of the trip home.

So, yes, let your credit card company know if you are going to be doing unusual things with the card.

tanstaafl.