Many Americans have objected to the fact that, for instance, when Trump travels to one of his golf courses, taxpayers must foot the bill (which earn profits for him) for rentals and accommodations for Secret Service and other staff.
A more troubling profit is earned by the President from his hotel in Washington which does considerable business catering to foreign governments that spend there lavishly in hopes of currying favor from the administration.
Many legal experts contend that Trump's continuing ownership and profit from businesses like the hotel violate the Constitution's prohibition on presidential emoluments. That provision prohibits money and gifts passing to a President from both foreign and domestic governments.
Accordingly, Trump has been sued in several federal courts by a variety of parties, some who are individuals, some that are businesses, and some state and local governments. One suit was thrown out on technical grounds but is currently being appealed.
This week, another one of those suits took an important step forward when a judge tossed out the President's arguments that the case should be dismissed (details here). The case will now move on to the next step of defining what exactly constitutes an emolument and whether Trump has violated the prohibition against them.
Trump promised repeatedly to step away from his businesses totally (details here) and, not surprisingly, he has repeatedly broken that promise. He continues to be briefed on and directs his private business operations and has regularly used the Oval Office to pursue new business opportunities, including foreign developmemts, which he had promised to end -- another promise which he broke.
If one or both houses of Congress fall out of Republican control in this year's election, we can expect this is an issue that will gain much wider attention with the possibility of Congressional hearings on how Trump may be violating the law by continuing to profit from and direct his various businesses. It's an issue that Congress should already be addressing, but sadly, the Republicans now in control are doing absolutely nothing.