Markets have grown concerned about the rapid pace of borrowing and spending by the federal government, but if Trump successfully addresses the US debt problem, stocks could be on the verge of an "everything rally," market veteran Ed Yardeni said on Monday.

So far, the CBOE Volatility Index, which measures expected swings in stock prices, remains near the low end of its post-pandemic range.

But this week Trump moved closer to home, threatening 25% tariffs on all goods imported from Mexico and Canada and tying the tariffs to demands for better border control by both countries.