I think existance of such a name is offensive for all the nations mentioned and thus should be uprooted from English language. It perpetuates the idea of Slavic subhumanness that existed in Western European countries even before. In some German cities, up to XIX century no Slav could be a citizen, and even in XIX century German scientists coined a proverb "Slavica non leguntur" ("Texts by Slavic authors should not be read"). This paved a way for Hitler's politics who wanted to create his lebensraum in Slavic countries - especially Poland, but also Ukraine, Belarus and Russia.
The existance of anti-Slavic tendencies in Western culture is often neglected, because Slavs are part of the same civilisation. They are "ours", but worse kind of "ours". But it makes it easier to attack them, because it is not seen as racism, while similar remarks directed towards Jews, Pakistanis etc would be impossible.
This allowed anti-Polish rhetorics of Farage and even Cameron.
The use of word slave is only a symbol of this internalised feeling of disdain towards Slavic peoples and superiority that exists in some western countries.
Discuss.