Revised Standard Version places a paragraph break here, which is helpful.

Those of the Jews who are called Hasideans, whose leader is Judas Maccabeus: For Hasideans see the comments on 1Macc 2.42. Following its rendering of Hasideans there, Good News Bible here translates “think of themselves as devout and patriotic.” This is a good approach, and spares the reader another unfamiliar term.

Are keeping up war: Alcimus does not really say that Judas’ followers “love war” (Good News Bible), but that they “are keeping the war alive” (New English Bible), “feeding the flames of war” (Goldstein), “constantly fighting.” They may be described as “violent men.”

And stirring up sedition means they are trying to get other Jews to join them in their rebellion against the kingdom.

And will not let the kingdom attain tranquility: Good News Bible is misleading here. The kingdom is Demetrius’ empire, not the Jewish “nation.”

Here is an alternative model for this verse:

• “A man named Judas Maccabeus is the leader of some Jews who think of themselves as devout and patriotic. They are violent men who are trying to get the Jews to rebel against you. Your kingdom will have no peace as long as they are active.

Quoted with permission from Bullard, Roger A. and Hatton, Howard A. A Handbook on 1-2 Maccabees. (UBS Helps for Translators). New York: UBS, 2011. For this and other handbooks for translators see here.