That's not an accurate paraphrasing. Of course when it comes to "foreign private commercial information or trade secrets" it is the sovereign right of the U.S. to "do whatever the fuck we want." The paraphrased language actually makes a concession: we will only use this information for security purposes as opposed to commercial purposes.
They obviously wouldn't lie, would they? And I guess abuse also never happens.
I thought the point of this was to implement mechanisms that would make occurrence of abuse less likely, instead they're just trying to calm people down.
The only lie would be if they said they were going to stop monitoring foreign Internet comms completely.
Beyond that, if you're assuming the government will lie as a matter of course then it doesn't matter what Obama said in his speech, as there's nothing he could have said to conclusively guarantee anything you'd want.
In other words, to say that the U.S. can't say tap international fiber cables and record all French traffic, you must be able to point to a treaty where we agree not to do that. And even then, since nobody can enforce that treaty against us, we follow it only to the extent we find it convenient. Sovereign nations exist amongst themselves in a state of nature, and those are the rules of nature.
Sovereignty and the lack of some treaty preventing some behavior X does nothing to prevent other sovereigns from becoming angry and or retaliating in kind. Doing something 'because we can' does not make it wise.