"The president was not suggesting any illegality," insisted White House Counsel Bob Bauer. In other words, when Obama said "one of the largest groups paying for these ads regularly takes in money from foreign sources," he was not implying any connection between the ads and the money. He was just stringing sounds together randomly.
In terms of logical force, he might as well have been. Even if the U.S. Chamber of Commerce (or, as ThinkProgress calls it, the "Foreign-Funded 'U.S.' Chamber of Commerce") were a wholly owned subsidiary of a giant international corporation, noting that fact would do nothing to refute the group's criticism of Democratic policies.
Deploying "foreign" as a term of opprobrium in the context of an ad hominem attack does not exactly burnish Obama's credentials for the Nobel Peace Prize, which he won last year after less than nine months in office based on nothing more than the hope that he would be a less ugly American than his predecessor. Nor does it suggest that Obama has drawn a moral lesson from his own experience with such baseless attacks. But it is of a piece with his frequent complaints that the First Amendment allows too much speech of the wrong sort.
"If we just stand by and allow the special interests to silence anybody who's got the guts to stand up to them," Obama said in his Maryland speech, "our country is going to be a very different place." What the "special interests" are actually doing is speaking, and the president regrets that they have the freedom to do so. Who wants to silence whom?