Steven Rattner says artificial intelligence will be a major contributor to the economy, but the market still does not know exactly who the winners and losers will be. As Big Tech pours money into AI infrastructure, investors are starting to demand a wider margin of safety from companies borrowing to fund massive capital spending. Rattner says cheaper Chinese AI models could also reshape the competitive landscape, especially if companies can easily route tasks to less expensive models. At the same time, rising Treasury yields, inflation, federal deficits and higher defense spending are pushing borrowing costs up a shift that could weigh on AI valuations, private equity deals and companies whose expected profits sit far in the future.