A fair number of countries did have lockdowns that successfully eliminated (as in: completely eliminated the virus within their borders) the virus within weeks. China is the elephant in the room (local elimination by about April 2020), but there are several other countries that did the same thing (such as New Zealand, Australia, Vietnam, Singapore, Taiwan).
On the assumption that you're an American, your country was not organized enough to couple a lockdown with effective contact tracing and mass testing, which is what other countries did to eliminate the virus.
On the assumption that you're an American, your country was not organized enough to couple a lockdown with effective contact tracing and mass testing, which is what other countries did to eliminate the virus.