The U.S. Commerce Department has up-to-date websites

The U.S. Department of Commerce is tracking retaliatory tariffs against U.S. steel and aluminum tariffs. So far Canada, China, the EU, India, Japan, Mexico, Russia and Turkey have imposed or threatened to impose retaliatory tariffs.

The International Trade Administration unit of Commerce is tracking retaliatory tariffs. This webpage provides foreign tariff responses by country: https://www.trade.gov/mas/ian/tradedisputes-enforcement/retaliations/tg_ian_002094.asp

This webpage provides a retaliation product coverage matrix by six-digit HS17 product codes, with links to each country’s detailed World Trade Organization explanation: https://www.trade.gov/mas/ian/build/groups/public/@tg_ian/documents/webcontent/tg_ian_005571.pdf