BERLIN (AP) — It started out simple enough: German Chancellor Angela Merkel criticized constitutional changes that have been made in Hungary. But Hungary’s leader not only objected, he also found what he called a veiled reference to Adolf Hitler’s occupation of his country in 1944.

The result? Tensions between Germany and Hungary have flared, and if there is one lesson to be learned it may be that the word “cavalry” should be left out of all future back and forths.