I have mixed feelings about linguistic purism. It’s a fascinating topic – for example, did you know that one of the reasons why Icelandic is so difficult to learn is because there are not many modern loanwords in the language? The official policy of the government is to create new words from Old Norse roots (technology-related words are invented from old words, so unlike in other languages, the word for “internet” in Icelandic doesn’t actually resemble the English word at all, at least according to what I’ve read). A similar phenomenon is present in Croatia – after the breakup of Yugoslavia, Croats have promoted words with Slavic roots over their Serb variants (which sometimes have Latin or Germanic roots).
The one problem I have with linguistic purism is that language changes. A living language organically changes and grows. Usually this is not inherently a bad thing or a good thing; it is simply a fact of life. Old English is now unintelligible to an English speaker (unless one specifically studies it, of course) and Middle English can be pretty strange, too.
What prompted this post was a blog entry I found on a Russian-language blog. It contains a list of 235 loanwords that have Russian equivalents. From what I can tell, the author was mourning the fact that foreign words like арест [arrest] and бизнес [business] have displaced their Russian equivalents (задержание and дело, respectively).
In general, people who rail against loanwords and want to expel them from a language are fighting a losing battle. Unless a language is isolated and has a government-backed policy of linguistic purism (like Icelandic), such efforts to keep a language “pure” are doomed to failure.