What does “Safety net in the coffin” mean?

There was the phrase “the safety net in the coffin” in reference to Mr. Paul Ryan, running mate of Republican presidential candidate Mitt Romney in Maureen Dowd’s article, titled “Cruel conservatives throw a masquerade ball” in New York Times (September 1 issue). It reads:

As the writer Dermot McIvor notes, Ryan has “the so sincere, so phony air of a gloomy Irish undertaker standing outside the funeral parlor where you’ve come to plant your mother, shaking his head consolingly and giving you that firm two-handed Irish handshake.” Except with Ryan, it’s the safety net in the coffin.

I thought “the safety net in the coffin” a weird, but amusing combination of a positive word – safety net, and an uncomfortable word – coffin, but I don’t understand what it implies.

Why on the earth, a coffin requires the safety net inside it? To hold the corpse gently and warmly? It’s impossible.

Does it describe Mr. Ryan’s disguised harshness and indifference to the poor and illegal immigrants under the cloak of a sincere visage and consoling air?

What does “Except with Ryan, it’s the safety net in the coffin” exactly mean? Why is it “Except with Ryan”?

The sentence could be expanded this way:

Except that with Ryan (unlike with the gloomy Irish undertaker), what's in the coffin is the social safety net (rather than your mother).

(The social "safety net" being government entitlement programs for the elderly, poor, and disabled: Medicare, Social Security, Welfare, Medicaid, and so on. Actually, Wikipedia says it only includes the programs for the poor, but I'm pretty sure that Medicare and Social Security are frequently included in the "safety net" as well.)

Edited to add: To make this a bit more explicit — there is no phrase "the safety net in the coffin". This is a sort of cleft sentence; "it's the safety net [that's] in the coffin" means roughly "the safety net is in the coffin" or "the safety net is what's in the coffin" or "what's in the coffin is the safety net".