PP, when Wilhelm Marr first used the word "Antisemitismus" in his 1879 pamphlet 'Der Sieg des Judenthums über das Germanenthum' he coined that term as a euphemism for 'hate of jews'. He used it in a racial sense and his target group were the (German) Jews and nobody else.

You are right, he could have used a better term for what he meant but he hasn't and since that year this word has been used in this sense and in no other until very recently.

Wolfgang