The Jews do not believe that Jesus was the Messiah, let alone G-d. For Judaism, the Messiah is not meant to be G-d since G-d is believed to be a unique non-corporeal, spiritual entity Who cannot assume human flesh. The Unity of G-d is one of the thirteen principles of faith in Judaism. In addition, Jews insist that Jesus did not fulfill all, or any, of the conditions of the Messiah. Moses warned the Jewish people many times that anyone who claims to be the Messiah and also G-d is not the true Messiah. Neither do the Jews believe that Jesus came to save the Gentiles. (They do believe Jesus was a good man, an esteemed Rabbi, perhaps even a Prophet.) In fact, the whole notion that anyone–including the Messiah–can save someone else’s soul is foreign to Judaism. That is not regarded as the purpose of the Messiah: the purpose is to bring peace on Earth. Also, the coming of the Messiah does not terminate Jews’ obligation to follow the Mosaic Law. Most Jews are still awaiting the Messiah (again, this is one of the principles of faith), though not all Jews believe in this. With regard to salvation, Judaism believes it to be personal and dependent on one’s own good deeds; there is no such thing as salvation by proxy according to Judaism. Further, salvation is not even the main idea in Judaism. Indeed Jews are forbidden to focus on speculation regarding the afterlife; they are instructed instead to pay attention to leading a good and moral life in the here and now, and to trust in G-d to take care of the rest. The notion of an afterlife in Judaism is a somewhat later invention (which has some evidence in the Hebrew Bible), and, to this day, not all Jews believe in an afterlife even though resurrection is another of the thirteen principles of faith. Finally, the idea that the Holocaust is a punishment from G-d is not a Jewish concept at all; neither is it a Christian concept. G-d does not work that way.
I realize that you, as a Catholic and a Christian, do not have the same beliefs as I, as a Jew, have. I didn’t mean for my writing to sound like an apology for Judaism, but I was trying to answer your question the best way I can. Even though I may disagree with your most essential beliefs regarding Jesus and the Trinity, I have the greatest of respect for them, just as I have respect for other religions and their beliefs. I hope you can, too, have respect for mine.