If the sea level is rising 12 mm around the Marshall Islands, it is rising 12mm in the rest of the world as well.
Water seeks its own level. I learned that in Junior High Science class.
The Panama canal has locks for a reason.
“On average, the eastern seaboard sees 3 mm per year of higher seas, according to a recently published article in Nature’s Scientific Reports....There are three primary reasons why the east coast of the United States is seeing higher relative seas. Two of which involve sinking of the east coast into the sea...These three factors have caused sea level to rise about 2 feet (60 cm) since the 16th century when most coastal communities were founded.”
From Global Warming Friendly Wiki:
“Sea level rise will not be the same at every location on earth, with some locations even getting a drop in sea levels. Local factors include tectonic effects, and subsidence of the land, tides, currents and storms. Sea level rise is expected to continue for centuries. Because of long response times for parts of the climate system, it has been estimated that we are committed to a sea-level rise of approximately 2.3 metres (7.5 ft) within the next 2,000 years for each Celsius degree of temperature rise.”
https://en.wikipedia.org/wiki/Sea_level_rise
I’m thinking we can adjust. Over the next couple thousand years.