It's interesting to see what the Delta variant is doing in the UK. The UK has a vaccination rate similar to the US and their cases had gone way down. The Delta variant got into the UK sooner than in the US, and it has become the dominant strain. Now the case loads are going up again in the UK significantly.
I think we are looking at a similar uptick soon. The one difference is that, from what I read, in the UK they were pushing lots of people to get a single dose of vaccine and then waiting to give the second dose for much longer - in the US, we pushed people to get their second dose either 3 weeks (Pfizer) or 4 weeks (Moderna), so we have fewer people wandering around with only one dose in their bodies. The Delta variant seems to be able to overcome single-dose immune systems pretty easily.