Even as the Trump trade delivers significant gains to U.S. stock market investors, most notably the Apple (AAPL) shareholders set to benefit from a $100 billion share buyback, U.S. equity markets are trading about where they were back in November 2017.

Action Alerts PLUS holding Apple is the latest major corporation to return cash to its shareholders after the tax cuts, including, just this month, Broadcom (AVGO) ($12 billion), Facebook (FB) ($9 billion), Textron (TXT) ($2.6 billion) and American Airlines (AAL) ($2 billion).

Facebook and Textron are also Action Alerts PLUS holdings.

In all, stock buybacks have reached $387 billion since the tax cuts were passed, or 58 times more than the $6.7 billion of announced or estimated one-time bonuses or pay increases corporations will give to workers, according to a group called Americans for Tax Fairness, in a press release.

That shouldn't concern stock investors, who are entitled to participate in the profits of the corporations they own. What obviously is bothering investors, though, is where the markets go from here. After the Fed kept benchmark interest rates unchanged, the Dow Jones Industrial Average fell for a fourth straight day to a one-month low. And earnings season has been good, too.

Emphasis on "has been."

Investors may be realizing how transient the Trump trade might turn out to be. Two of the pillars that have supported the markets so far - lower corporate taxes and the reversal or weakening of environmental, financial and consumer protection regulations, are creatures of the current Congress and administration and can easily be replaced by a future Congress.

In fact, California Governor Jerry Brown has said that California would join 16 other states in suing to halt the Environmental Protection Agency's plans to freeze increases in auto fuel-efficiency standards modeled on California law. It's an example of how Republican rule in Washington is sparking resistance in the states - this is the 32nd lawsuit against the Trump administration that California has filed or joined.

Since it's now May, that means U.S. congressional elections will happen in just six months, with the distinct possibility that the Republican majorities in both houses of Congress will pass into history.

In the meantime, there doesn't seem much on the horizon coming from Washington from now until November that could provide a boost to markets. President Trump's vow to present $1 trillion in infrastructure spending are evidently going nowhere, even though such a plan could support thousands of new jobs and pump money into investments that could benefit the country for years to come. Similarly, there's nothing happening to revise or fix the healthcare system, the education system or the veterans' administration, to name a few.

On the other hand, there's another character in Washington who might have something to do with investor confidence, and who has yet to shuffle fully onto the national scene: Special Counsel Robert Mueller. Whether the results of his probe boost confidence in profit prospects for investors, in one of the President's trademark expressions, we'll just have to see.

Market investors have to look for prospects for profit that will arise in the coming quarters or years, and it's becoming clearer that those prospects are in danger of being shortly foreclosed. The Trump trade may be closer to its end than its beginning.

To contact the writer: john.pickering@thestreet.com. On Twitter: @johnpickering16.

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