If you want your ads to only appear in the US, you would create a campaign in Google Ads that only shows ads in the US. This works for the most part. However, many advertisers are still getting clicks outside of their targets areas even with Google ads own geolocation exclusion settings:
Therefore, we've built a country blocker into the ClickCease dashboard as a second line of defense. And it should be used as such. Your primary way of only showing ads in certain countries is still to set your campaigns to only show in certain countries. If you see that you get clicks from outside those countries, then you should use the ClickCease country blocker to help.
How does it work exactly?
The blocker will check the country of origin of each click. If a click comes from a country that is currently excluded, that IP address which generated that single click will be blocked on its first click instantly. By doing so, the IP will be prevented from seeing and by extension continue to click on your ads and drain your advertising budget.
For instructions on how to utilize the feature, see here