Rule No. 2? You never know when an unexpected geopolitical or market-moving event might happen, so be prepared.
For example, Cramer has been guiding that Commerce Secretary Wilbur Ross might recommend that President Donald Trump use Article 232 of the Trade Expansion Act to prevent Chinese steel dumping.
The article reserves the right to protect key domestic industries, in this case steel, for national security purposes. By invoking it, the United States would effectively push back against China's practice of artificially suppressing steel prices.
The move would "be a huge positive for the domestic steelmakers, but there's so much collateral damage. It will hurt the stocks of our international companies that do a lot of business in the People's Republic as investors start worrying about Chinese retaliation," Cramer said. "Something you need to keep in mind is this retaliation."