It doesn’t keep jobs, it cost jobs in the overall economy.
It’s but one law in a myriad of anti-US-business laws. One of the biggest is having the world’s highest corporate tax. The regulations out of the unaccountable agencies designed to “protect” the worker are the trunk of the mountain.
If you like your job going to a Third World country, by all means vote to abolish the American merchant marine.
Money isn’t everything and this is not strictly a dollars and cents issue. Nor should it be.