However, I donate to Jews for Judaism.
It's rather telling that some Christians cannot support Israel without wanting to convert all Jews. One wonders if that support is really true or not.
What's lacking in this discussion is an understanding of just who the Messianic jews are and what they are about. The "spiritual roots" of Messianic Jews go back to the fact that the early "christians" were almost all Jews. As their message spread, more and more gentiles were drawn into (lured into?) their community, and over time became first a majority and then an overwhelming majority (the first "Church Council" was called to settle the question of whether or not it was possible for a gentile to be a christian). Early christianity was very judaic, with celebrations of the Jewish holidays and shabbat.
As the gentiles began to dominate, there arose divisions, with many of the Jews "holding back" from full participation with the gentiles. The gentiles, in turn, grumbled about the jewish practices of the Jewish followers of Jesus. These controversies continued over 200 years until the Council of Nicea in the early 300's, at which time Christian Jews were ordered to stop celebrating passover and other Jewish holidays and rituals.
Meantime, the Messianics had become increasingly isolated from mainstream Judaism, one of the major divisions coming, interestingly enough, when Rabbi Akiva proclaimed Simon bar Kochba to be the Messiah, but the messianics rejected him as a false messiah. The Nicean showdown marked the beginning of the end for the early "Messianic Jews." They were basically forced to choose between a completely gentilized Christianity or complete exclusion. By the year 400, "messianic Jews" as a movement had disappeared.
Messianic Jews of today generally reject post-Nicean christianity, wanting to return to a purer, simpler, more Hebraic form. They naturally find their biggest welcome among christians from radical Protestants who likewise reject much of the traditions of the greater part of the Christian era.
Christians seeking to evangelize among Jews are frequently misunderstood by Jews who appeal to the persecutions of the past as a rationale for not proselytizing. It is not often understood that the evangelists of today stem from groups that have stood against religious and especially persecution by christians for centuries. The Evangelizer of today is the descendant of those who were burned at the stake with the Jews. He is not likely to be swayed by arguments that blame him or his ideas for the burning, since he has a long and storied history of resistance against christian persecutors.
The Messianic Jews of today see themselves as the inheritors of the early christianity and are about the project of restoring it. Whether they should or whether they should not, it is not more than ludicrous to portray them as conniving tricksters seeking to kidnap ignorant Jews and force them to believe something against their will.
Disclosure: I'm not Jewish, I believe in Jesus. My wife is Jewish, and she believes in Jesus. She's from a very large family and I'm related by marriage to what seems like half the Israeli Army. I did not "trick" her or "trap" her, she decided upon this course herself 7 years before we were married. My kids learned Hebrew, we celebrate the holidays, and my wife is the "evangelizer" while I do most of the worrying about offending people.