‘Sanctuary’ explores the politics of prudence
The issues surrounding Moclan culture have been slowly and steadily building since "About a Girl" last season, and have continued to magnify ("Primal Urges," "Deflectors") throughout this season. They reach a boiling point with "Sanctuary," which is an effective and involving drama that falls back on a number of classic Trekkian elements, including the impassioned public hearing and the tense diplomatic crisis.
While one could argue that we’ve perhaps seen too much of the Moclans over these first two seasons, I would instead argue that what the writers have done is build a solid arc across a series using an episodic format. I’m reminded of the way Worf’s discommendation arc and the Klingon civil war played out in the middle seasons of TNG.