What will happen to the U.S. economy if President Trump fails to get big win on cutting taxes? Not much, not much at all.

So says the chief global economist at Bank of America Merrill Lynch, one of Wall Street’s preeminent financial firms.

Ethan Harris contends the U.S. will do just fine regardless of whether Congress passes the first major overhaul of the tax code since 1986. He says low interest rates, the healthiest financial system in years and, perhaps most important, a revived global economy will all act to keep the U.S. on a steady growth path.

“By some accounts, tax cuts are not only very likely, but they are also critical to continued strong growth,” Harris wrote in a report. “By contrast, we not only assume no cut or reform, but we also expect solid U.S. and global growth anyway.”

Trump has repeatedly said he thinks U.S. stocks are responding favorably to his proposals and that a reduction in taxes will drive markets and the economy to fresh heights.

Here's what Trump's tax plan means for the stock market

Harris acknowledges U.S. stock markets could suffer a modest decline, at least temporarily, if the tax overhaul falters. Yet he suggests the role of promised tax cuts on the record surge in U.S. markets is overblown.

In the past year, for instance, a global “all-cap” stock index has posted a 20% increase just like a similar U.S. all-cap index, Harris noted. In his view, that shows the surge in U.S. stocks is neither isolated nor driven by Wall Street’s fervor for tax cuts.

The Dow Jones Industrial Average DJIA, -0.87% , the S&P 500 SPX, -1.11% and the Nasdaq Composite COMP, -1.07% all closed at record levels on Friday. The Dow has set a record 56 times this year through Friday, while the S&P has done so 51 times. The Nasdaq Composite’s 63 record closes in 2017 is the most ever for a calendar year.

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Investors have also been conditioned by the recent failure of Republicans to kill off Obamacare to take a “show me” approach to Washington law-making, Harris argues. The bank’s latest survey of global investment-fund managers shows that more than two-thirds expect little impact from tax cuts.