What were the groups called when Islam split during the Safavid Empire?

What would lead a historian to consider two events to have a relationship of correlation rather than causation

The chinese exclusion act was the first significant law restricting immigration into the united states. why do you think the us government singled out chinese immigrants in particular for exclusion?

Over the years, the colony of jamestown failed to establish peace with powhatan american indians. make itself a permanent colony. grow enough tobacco for export to europe. establish a representative government.