know there is nothing to worry - what does "know" mean here?

Question

I don't understand the use of "know" here. Who know? Does "to the American people — know there is nothing to worry about" mean "to the American people — (you should) know there is nothing to worry about"?

The problem is that I feel "you should" has a tone of more commanding than persuading. Perhaps with only "know" there the tone would be euphemized. I am not sure.

What does "know" mean there?

Biden tweeted 2h ago:

Today, I received the COVID-19 vaccine.

To the scientists and researchers who worked tirelessly to make this possible — thank you. We owe you an awful lot.

And to the American people — know there is nothing to worry about. When the vaccine is available, I urge you to take it.

Answer 1

I don't think he's saying You should know. It sounds to me more like Let it be known. A sort of proclamation.

It's the same imperative mood of the verb that appears in the Bible. For example:

This know also, that in the last days perilous times shall come.

Perhaps it's a question of the image he wants to project. Boris Johnson would probably stammer endearingly: "I would ask you all to bear in mind that there's nothing to worry about."