Any assessment of Zuo Zongtang's effectiveness as an organizer and operational commander will generally be quite positive. However, this should be balanced with an understanding of both the specifics of his methods and the goals his campaigns aimed to achieve. During his time in Hunan under Zeng Guofan, Zuo established a reputation for his 'hearts and minds' approach to conflict, involving the army in rebuilding infrastructure when not in combat.
In the northwest and Xinjiang, he also aimed to reduce the strain on local finances and resources by ensuring a steady flow of money and supplies from the imperial centre. Meanwhile, his 'hearts and minds' strategy seemed to target mainly Han Chinese sentiments, considering his oversight of massacres of Muslim troops and civilians, as well as his deliberate banning of Jahriyyah Sufis (known to Qing authorities as the 'New Sect').
Zuo 'appears to have truly believed in the mission of making Xinjiang something beyond a military colony,' but this 'beyond' referred to creating a settler-colony where Han Chinese would be deliberately introduced to exploit the region's resources and further disrupt its indigenous populations. He also stripped the local Turkic population of the concessions to local autonomy they had before the 1864 revolt, further hindering their ability to resist Qing and later Chinese overlords.
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