The following is quoted directly from the Chofetz Chaim A Lesson A Day, page 204:
"The Mishnah (Avos 5:20) contrasts machlokes l'sheim shamayim, disputes for the sake of heaven, with one that is not. The former is epitomized by the disputes of Hillel and Shammai whose differing views in the matters of halachah are reverently studied and pondered generation after generation as eternal components of the Oral Law. the latter is epitomized by the dispute of Korach, whose personal feud against Moshe Rabbeinu earned him an untimely death and eternal dishonor. As the Chofetz Chaim notes in his preface to Sefer Chofetz Chaim, one whose sinful talk fuels strife transgresses the prohibition, "that he not be like Korach and his assembly" (Bamidbar 17:5, seee Sanhedrin 110a).
To the Jew, intellectual disagreement in a common search for truth is an integral part of life. As a spiritual, thinking people, Jews are forever involved in discussion of ideas.
Conversely, personal bickering, jealousy, and competition are signs of immaturity and weakness. They have no place in the world of the Jew.
The difficulty, however, lies in our tendency to transform every dispute into an ideological one. Korach, too, came with a philosophy: that all Jews are equally holy, and thus there is no justification for one family, Aharon and his Kohanim descendants, to be above everyone else.
The Sages teach that Korach's argument was rooted in jealousy, resulting from his having been passed over for the position of prince of his Levite family.
Before embarking on an ideological campaign against others, one must ask himself: "Am I honestly promoting the cause of truth, or am I involved in a personal feud disguised as a n ideological debate?"
Ideological disagreement should never lead to personal animosity. When Torah scholars disagree, their dispute is over ideals, and is never personal. When a scholar is involved in a dispute, his followers must be careful not to become involved in a matter that is not their own, and certainly should avoid character assassination and personal hatred towards his opponents."
From this Torah principal, we learn the pitfalls of human nature when discussing ideological matters - that we can become ego-involved and cause harm rather than the good that may be intended.
Likewise we learn that those who wish to cause strife because of hatred or jealousy might argue their case on an ideological level in order to rally support for a feud based on a much lower level impulse for which they might otherwise be able to interest others.
Rabbi Frand speaks about the importance of not involving oneself in disputes that are not for the sake of heaven. The pitfall, he says, is that for us, every dispute becomes "not for the sake of heaven" but rather for the sake of winning. It is for this reason that staying away from disputes all-together is recommended.
Certainly amongst all the varying practices that Jews hold today, we can see many reasons to agree to disagree and make peace, just for the sake of peace itself. Doing so unifies us as one people. When the Moshiach comes, he will answer all our questions on the technical points. But to receive the Moshiach, we need to unify.