Fannie Mae-No Politics (FNMA)

[Wise Man]

It's called "UST backup of FnF". Keep the fancy names

"this looked like a guarantee or insurance policy"

, for the people that have never read the Charter Act or ignore the Mortgage Guaranty Securitization business, like THE FEDERAL ACCOUNTING STANDARDS ADVISORY BOARD that you mention.
A UST backup as a last resort, as expressly written in the section Purposes that also contains their Public Mission.

The operations thereof shall be financed by private capital to the maximum extent feasible

The operations are financed either by debt or Equity. FnF needed Equity, so, spot on, they issued SPS to reflect the debenture with the taxpayer (obligations in respect of Capital Stock), that must be paid back asap.

Therefore, this excerpt is telling you that, at some point, it would be necessary to activate the "Authority of Treasury to Purchase Obligations", in exchange for their Public Mission: take on more credit risk, not appropriately compensated.
This changed with the 2011 Privatized Housing Finance System chosen for the release from conservatorship: "UST recommends increasing the guarantee fees and subject to capital standards (Basel) that reflect their risk." (Source)
So, no subsidized g-fee anymore. The preps for a Charter-revoked endgame.

Notice that the number (2) in Purposes, could be a mandate to tap the private capital markets in the first place, which is what FnF did in the period 2007-2008 with massive issuances of JPS and common stocks.
However, at some point, when the crisis struck, the Treasury refused to comply with its part in the Charter Act, or is doing it concealed (Separate Account)
The idea that the Equity holders can't benefit from a UST backup of the enterprises they own, is related to fraud and an attempt to con the Equity holders, rather than Communism.

Finally, if HERA amended the Charter Act, then it's no longer HERA. Skip it and go straight to the Charter Act because the amendment is already included.

The HERA legislation granted temporary authority to the Treasury to purchase obligations of the Enterprise

You want to conceal that the UST backup of FnF inserted by HERA in the Charter Act, is duplicated when there was already the original UST backup at rates similar to Treasuries, limited to $2.25B, but updated with this 2nd UST backup with an unlimited amount, and subsequent SPSPA.
The Congress should have updated the outdated $2.25B, instead of 2008 HERA. A limit established more than 60 years ago when Fannie Mae had only 800mll in debt.
Therefore, there are 2 UST backups of FnF, and you want to conceal that they show up one below the other in the Charter Act. Both with the same name: "Authority of Treasury to Purchase Obligations. Terms and conditions."

No problem! Obviously, the original will prevail (estimated 0.5% spread over Treasuries. Weighted-average 1.8% cumulative dividend on the SPS). And the one with unlimited yield has been used for a Separate Account (10% and NWS dividends), with flaws, as it was a TEMPORARY authority (Deadline December 31, 2009), but it was related to purchases. This is why the SPS LP has been increased (Securities Law violation) instead of issued, to evade purchases and the deadline. Punitive damages arise.