Fortunately for the Irish and Jewish waves, they managed to get themselves into the middle class before welfare arrived.
Being married is work. You have to put up with the annoying and neurotic behavior of your spouse day in and day out. If you're poor, and the welfare benefits, all added up, come out to more than a husband's take-home pay, a bunch of women are going to decide to not bother getting married
A good chunk of the uptick in marriage that's mentioned in the article is likely caused by the current limit on welfare benefit duration -- one of Clinton's few redeeming legacies. If the welfare checks stop after 5 years, you suddenly find out its good to have somebody sticking around to help pay the bills and raise the kids
It was actually the Republican congress that forced him.