From Nikkei Asia: How Vietnam went from pandemic hero to COVID shambles

It is true that this time last year, Vietnam was a Covid success story, and that this year it has been much more of a disaster.  But aside from that, I disagree with many of the other assumptions in this article.  Vietnam did not get complacent.  They shutdown everything as aggressively this year as they did last year.  It's just that the Delta variant was so much more contagious, and spread so much quicker, that the shutdowns haven't worked this year.  (Or rather, the shutdowns haven't eradicated the virus, as it did last year.  I'm sure they've mitigated the contagion.)

Furthermore, Vietnam's leaders did not assume that a large scale vaccination program could wait.  Vietnam did not have access to vaccine, and is still struggling to get access to the vaccine.