Fannie Mae / Federal National Mortgage Assctn Fnni Me (OTCBB:FNMA) and Freddie Mac / Federal Home Loan Mortgage Corp (OTCBB:FMCC) have dominated the debate on how the government should support the housing market with banks, affordable housing advocates, private shareholders and free market purists all pushing their point of view. But alongside this tangled conversation, Ginnie Mae has tripled its mortgage-backed security (MBS) portfolio from less than $500 billion at the start of the financial crisis to $1.5 trillion last month, earning a profit every year for the last two decades, and is now building the groundwork to become even larger….