What is a Federal Loan Guarantee?
Is that like when I co-signed my stupid brothers car loan and ended up paying for it?
No you did that somewhat willingly
A federal loan guarantee is when a borrower obtains a loan from a private entity (a bank etc.) and, as part of the loan agreement, the federal government (translation: the taxpayers) promises to reimburse the lender should the borrower than subsequently default. Of course, the government then attempts (not always successfully) to have the original borrower reimburse the government for any loses incurred. (Good luck in the case of Solyndra)