A combination of Weimar (a city in Germany and a name for the post WW1 failed German government) and America (the United States). Wei-Merica.
It’s a nickname given to the United States by certain right wingers who believe the nation is taken over by rampant degeneracy and economic collapse, similar to the Weimar Republic.
A portmanteau of "Weimar" and "Amerika". Used to describe the perceived similarities between the pre-World War 2 Weimar republic of Germany and the United States of today. These similarities may be the loss of social cohesion and moral values, a rise in crime, inequality, and a general alienation from the current state of affairs. These factors of instability led to the collapse of the Weimar republic and this is similarly implied by the use of the term Weimerika to be a possibility in the United States.
"A humiliating loss in war, rampant inflation, geriatric plutocrats running the show. Sometimes it really feels like we're living in Weimerika."