The frog in the pot metaphor. Increase temperature immediately and frogs jump out
Required:
Complete government incompetence. Great Depression levels of hyperinflation and starvation.
Jews' paranoia raised somehow to new levels of paranoia to pester Homeland Security to have authorities harass all citizens.
A mandated militarized force consistently abusing the people regardless of who they are.
Barriers:
Hope. The belief that "as long as I don't do X thing I'll be okay." You see this in the UK and modern Germany where idiots defend their lack of rights in favor of the jew regime controlling them.
Because they have - minor luxuries and necessities met. Abilities to feed, clothe and shelter themselves. Desperation not intense enough to fight back as in 1920s Germany.
Results:
Always have someone on the inside. Acquire lists of detainees. Find out which are National Socialist suspects. Raid facilities keeping them. The increased jew-obedient henchmen boots on everyone's necks would have unprecedented levels of converts to NatSoc.

Examples of what not to do: North Korea lies about their "Great Leader's" false victories. Tearing down NK government posters leads to imprisonment. Aiding towards "follow the regime and I'll be okay."
This means the collective jew paranoia must be so high that their intense hate of all non-jews causes them to harass every single one of us regardless of loyal to them or not.

Remember
Jews WANT all Caucasians bred out and extinct.
Jews WANT those that remain to be their obedient slaves.