No government that has elections is going to say they want herd immunity and expect to win a re-election. So far, the only country that declares this openly is Sweden. For the case of the US, the Democrat states and cities are leading the way to herd immunity starting with NYC which probably has already achieved effective herd immunity. We're already going into August, there's only 4 months left to finish developing and testing the vaccines and not to mention to manufacture the one billion doses, the minimum the world needs. So it won't happen until at least the middle of next year. The US is not going and can't do the type of quarantine and social distancing that countries that could control the virus are doing - mandatory wearing of masks in public and workplaces, compulsory quarantine in hotels and quarantine facilities for travellers and compulsory detention in covid facilities for all infected people until they are fully cured.