Answer:
French rule brought in modernization, industry, new cultural and social changes, a new religion and overall, it "westernized" the Vietnam.
However, the wars destroyed the nation, its property and population while the indegenous vietnamese scoiety collapsed and got diluted. the traditional way of life changed and all the economic, environmental and social problems of industrialization followed.
so overall, it had a negative impact on Vietnam. French Colonial Rule was bad.