protectionism works to protect what we have, not bring back what is lost.
Suppose you elucidate us further on economics, Octopus! An economy is a living, breathing, dynamic organism, as it really is an extension of human society, yet you seem to think of it as a static entity, like a bag of marbles to be merely hoarded or shared. If I PROTECT a flower in my garden, I just don't get to keep my one flower, I eventually get lots and lots more of them! Likewise, protectionism gets you more of whatever it is you protect as you've fostered a favorable environment for its growth.
As to tariffs, this one chart says all that needs to be said. Note the source.
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