The courts have historically been unlikely to see a Constitutionally-required affirmative permission in the fact that an additional restriction is not applied by Congress.

The fact that Congress has specifically granted permission under the Emoluments Clause to Presidents, at the latter's request, while the conflict statute was in effect wouldbsuggest stronglynthat neither past Presidents, nor, more importantly, the Congress has viewed the non-application of the conflict statute to the President as a grant of permission under the Emoluments Clause that makes more specific grants unnecessary.

OTOH, absent coverage under the conflict statute or some other statute establishing judicial remedies, there may an argument that there is no such remedy for a Presidential violation of the clause, and that the only remedy is via impeachment. That's probably the biggest weakness in an Emoluments Clause lawsuit.

On the gripping hand, a court ruling to the effect that the only remedy is by impeachment may create additional political pressure on Congress, which would probably have value to those bringing the claim, perhaps moreso than a judicial remedy that, e.g., forced Trump to give up past gains and avoid future gains through divestment.

This is a different issue. Trump is correct that the conflict of interest laws don't apply to him. However the emoluments clause is something else, and most constitutional scholars say that it clearly does apply. This doesn't prohibit conflicts of interest; it prohibits federal employees and office holders from receiving gifts, titles or emoluments from foreign governments. Profits from business with foreign governments would certainly be covered by this, as would beneficial terms on loans and, arguably, things such as building permits. You'd struggle to find a single non-partisan expert who would say that he isn't violating this right now, and even plenty of Republican lawyers agree.

The trouble is that impeachment is the responsibility Congress, and it would be a brave Republican congressman who would vote to impeach a Republican president right now.

Sure, but the courts enforce the constitution, not congress.

The issue isn't who enforces the constitution; it's what the constitution says. Congress has the power to decide which emoluments are okay. Assuming parent comment's interpretation of the law is correct (which it may not be), Congress has given blanket permission, in the same way that it has historically signed away large parts of its Constitutional war-making powers to the executive.

Congress hasn't given blanket permission. The law says that it's illegal for certain government officials to accept gifts etc. It doesn't say anything about whether it's legal for the president to accept them; it merely says that the president is not within the scope of that particular law.

There is an argument that the spelling out of cases in which it would be illegal implies that they're okay with it in other cases. See https://en.wikipedia.org/wiki/Exception_that_proves_the_rule...

You don't have to have a law for something to be legal. All actions are legal unless stated otherwise.

In the absence of any law, yes, it would be legal.

Constitution has a clause that prohibits it for any public official including the president (assuming for the moment that it is the meaning of the emoluments clause), unless Congress specifically authorizes it.

Congress additionally passed a law - 18 U.S. Code § 202 and § 208 - that regulates conflicts of interest among government officials. Its domain intersects with the Emoluments Clause somewhat, but it is not an implementation of the Emoluments Clause. It says that certain actions by people other than the president are illegal. Insofar as it intersects with Emoluments Clause, it is at best redundant (although even then it defines clear penalties, so not really).

But there's nothing in it authorizing the president to receive emoluments. § 202 does contain language excluding certain people from the categories of "government officer" and "government employee", which are the target of § 208; but this simply means that § 208, and prohibitions in it specifically, do not apply to those people. In other words, the law doesn't say anything about them. It most certainly doesn't contain any language explicitly authorizing emoluments. Here, see for yourself:

https://www.law.cornell.edu/uscode/text/18/208 https://www.law.cornell.edu/uscode/text/18/202

If we look at other past cases where the Emoluments Clause had to be dealt with, Congress specifically authorized such things, with clear verbiage to that effect. For example, here's the Foreign Gifts and Decorations Act:

https://www.law.cornell.edu/uscode/text/5/7342

Note the language: "The Congress consents to ..."

There's nothing even remotely similar in the law we are discussing.

The only real question for the courts here is whether receiving payment for goods and services from a foreign government qualifies as emolument or not. The originalist interpretation is in favor of that - this is one of those clauses in the Constitution where the Founders wrote a great deal about why it was there, and it's clear that their concerns were broad rather than narrow (preventing "foreign corruption" of all kinds).

Yes, and the constitution states otherwise.

Well then. My assumption of parent comment's correctness was wrong :-)

Courts interpret the constitution. I'm no lawyer, but "without the consent of the United States Congress" seems very clear-cut to me. It's up to congress, as per the constitution.