Because tariffs will affect the prices of goods, and maybe services as well, low-income people will be affected more than those with large incomes. Thus, a good thing to do would be to provide tax relief by increasing the standard deduction again.
The federal government is a big consumer of goods and there are companies that get government contracts and manufacture specifically for the government. Why not require those companies to use U.S. steel and aluminum? By doing so, tariffs could be lowered on steel and aluminum because one of the purposes of tariffs is to help those lagging industries.