Well for starters you don't have the benefit of comparing what happened to some hypothetical ideal plan. Trump's response and the subsequent outbreak were comparable and superior in many ways to the Western European response.
Second, it's weak because the media and the left were opposed to the travel ban when it happened. Now you want to say they were a month late? Please...
As far as testing, the CDC **** the bed on testing very early on. Not because Trump told them not to work on testing, but because they are incompetent. Ultimately that falls on Trump, but that isn't a problem with policy or response.
Now we are doing more testing than anyone in the world. And that's not good enough, if Trump wasn't such an idiot, we could just do 100 million tests a day and the virus would cower at the sight of all that testing. Silliness.
Finally, even with the benefit of hindsight the media can't even get it right. We are told in March Trump's biggest mistake is not getting ventilators. Two months later, everyone who needed a ventilator got one, and after realizing they are mostly ineffective against the virus, we are now the world leader in ventilators sitting in a warehouse collecting dust.