There are eternal ramifications for one group or the other depending on which senario is true. You think it's sad because Christian's want to talk about it. I think it's sadder that you would rather choose silence, than to explore the issues and discover the truth.
What if they were local Christians instead of Foreign missionaries, would that make a difference?
This thread is way off topic. The article isn't about evangelizing, it's about evangelizing minors.
Is it really an imposition on Christians to wait till the prospects are of an age to understand the message, and either understand or reject it? Why would you want to convert a 15 year old under the guise of, the example in the article, telling him Baptism is a Jewish ritual. I don't see this as a controversy.
Why do you assume that we haven't "explored the issues and discovered the truth"?
In my opinion, as in the opinion of all Jews, Jesus was not the son of G-d.
I have no opinion whether Christians, who are not Jews, have committed blasphemy by believing a liar or a madman was G-d and worshipping him. I further have no opinion whether Jesus was a liar or a madman. My understanding is that he was a religious Jew.
Observant Jews always aspire to obey G-d and follow his commandments. It is not easy. The Bible itself tells the story of how, after being liberated from Egypt, the ancient Hebrews (I should say "we" ancient Hebrews, since Jews are to see the exodus as though it happened to them personally) so angered G-d that they had to wander the desert until the entire generation of the exodus died out (except for two). Certainly, Jews have disobeyed G-d. So has everybody.
Local Christians trying to lure Jewish children to abandon their faith are as appalling, in a religious sense, as foreign missionaries who jet in to Israel to do the same. However, they may not be as contemptuous of the State of Israel as are the foreigners.