The NSA will never do that as it would be tipping their hand about whatever novel technique they reveal. In the past the NSA actually did provide some constants

The NSA will never do that as it would be tipping their hand about whatever novel technique they reveal. In the past the NSA actually did provide some constants that went into DES and people were suspicious as the constants weren't randomly chosen. Later on it came out that differential cryptanalysis would have broken the original constants but the NSA provided ones were chosen to thwart this. They clearly knew about it well ahead of it being discovered in academia. Then you have the NSA's shady dealings around Dual_EC_DRBG where there was speculation that this might be similar to when the NSA secured DES against publicly unknown advanced cryptanalytic attacks. Of course for Dual_EC_DRBG that wasn't the case, it was a malicious backdoor, nothing more. The question comes down to "Is this a repeat of DES or Dual_EC_DRBG?" and the NSA has poisoned the well with their previous attack on cryptography standards.