While I admire the work ethic of the JW's in sharing their faith and while I've found them to be fairly well-read in the scriptures, I've also found them to be very much limited to their own scriptural interpretations which, quite frankly, are less logical than mine.
Nobody can insult what you believe (especially at your own door) unless you allow it.
Rather than being disagreeable, I've usually found out I can agree to disagree with most faiths brands, as well as finding common ground.
Generally, with JW's, I find that asking them about their belief in not getting involved with secular politics then asking them how that is working out for them is the key to sending them away thinking.
The point of answering objections, Vigilanteman, is to open the mind of the JW to the truth. As a JW for 38 years, I can tell you that your question would be ineffective at getting them to think. They already believe that not getting involved in politics sets them apart as the “real Christians” who place their hope in God’s kingdom unlike “so-called Christians” (like you) who busy themselves “arranging deck chairs on the Titanic.”