Difficult countries for gaining citizenship and their requirements.
Vatican City: Citizenship for cardinals or Catholic Church officials.
Bhutan: 20 years residency, no anti-king or country activities.
Qatar: 25 years residency, limited naturalizations.
Kuwait: 20/15 years residency, Muslim, Arabic fluency.
Liechtenstein: 30 years residency (5 if married to citizen).
UAE: 30 years residency (3 for some Arabs, 7 for others).
Switzerland: 10 years residency with AC permit.
Relatives required, limited chances without Chinese family.
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