This is absolutely untrue, and is a very dangerous bit of nonsense to be spreading around.
Clearly the numbers will get updated with additional data, but the breakthrough infection rate for vaccinated people appears to be well under 1% at the moment. And the rate of vaccinated people who have a serious case or death is, of course, much lower than that.
If “effective” only means 100%, I suppose it’s not all that effective, but that’s a rather ridiculous bar to set.
Good thing I wasn’t trying to say that is the vaccine wasn’t 100% effective that it was useless. 
That breakthrough rate, as I understand it, if for breakthrough infections that result in hospitalization. There seems to be mounting evidence that fully vaccinated persons can and do contract and transmit the Sars-Cov-2 virus, but the vast majority do not show symptoms. The cases that do exhibit symptoms are much milder than unvaccinated persons. If you look at the UK, where the percentage of vaccinated persons is very high, but the transmission of the Delta variant is close to the same as in locations like Missouri, which has a considerably lower vaccination rate.
Unless I am mistaken, the CDC stopped monitoring breakthrough cases on May 1, before the Delta variant was even well established, so reports based on CDC information are not going to be very informative on this issue. I understand that the Delta variant results in virus shedding loads up to 1000 times that of the earlier strains. I would not be surprised that this also means that people who are exposed to the virus, but not at levels to cause illness (due to either vaccination or natural resistance) can shed the virus at levels that can infect others. Yes, the vaccine is very effective at preventing sickness, hospitalization, and death. I am sorry if some of you could not understand that. Believing that vaccinated persons cannot transmit the virus to others is, IMO, very dangerous.
Clearly, our best tool for combating this disease is vaccination. My point I was trying to make is that it would be a better strategy to drop the emphasis on masks and shutdowns (which aren’t going to be effective in the US, anyway) and concentrate on vaccination. We are already seeing Republican Governors and Congressmen calling for increased vaccination and I believe that not only that trend will continue, but the rank and file Magats will get the shot, particularly if it lets them go to restaurants, bars, and concerts.
It really doesn’t matter if the vaccine card is easy to forge. You have to assume that everyone, vaccinated or not, will be exposed to the virus going forward. There really isn’t a way to stop that as far as I can tell. Those who have been vaccinated will have a much better time of it. Those who are not will have a tougher time. A forged card will not keep you from getting sick, but it might get you in trouble with the authorities.
This is a mistaken understanding. The breakthrough infection rate is simply the rate at which vaccinated people are getting infected 2 weeks after their last dose.
If you check my cite, you’ll see the rate at which infections that result in hospitalization among vaccinated are much lower than the already low rate of less than 1% that get infected in the first place.
And again if you check my cite, you’ll see it’s not based on CDC numbers but on what independent numbers are available - so yes, it includes figures for Delta past May 1.
Not that those figures can’t change, but as of right now, the odds of a vaccinated person even contracting COVID, whether the Delta variant or not, is simply very low. Sure, we all see stories about it, but “vaccinated person doesn’t contract COVID”, though vastly more likely, is a much less interesting news story.
Again, please look at the cite. The information is there for the reading.
I have read it. Thoroughly. It does a good job of summarizing the available information and shows the benefit of the vaccination on preventing hospitalization and death. It does not, however, make any comment on how likely a vaccinated person will become a asymptomatic spreader. That is, become infected by the virus, but not show any symptoms and, therefore, not get tested, but is still capable of spreading the virus to others.
Settled? Do you have something that I can read that backs up your statement?