Betsey Stevenson and Justin Wolfers have an interesting working paper on the "driving force" in marriage and divorce changes. Stevenson and Wolfers are the Wharton School professors who cleared up the puzzle about the erroneous Census Bureau report that most marriages don't reach their silver anniversary.
One finding that they put in stark relief is that the marriage rate in the United States is at the lowest point in recorded history. Indeed, the marriage rate peaked in 1972, and has been dropping ever since. Americans still couple at high rates, but many of them are cohabiting rather than marrying. Most cohabiters think they will marry -- but they don't.
On the other hand, "Americans marry, divorce, and remarry at rates higher than in most other countries with comparable income levels." Compared to Canada, the UK, France, Germany, Italy, and Sweden, Americans are more likely to marry and more likely to believe in marriage. For example, only 10% of Americans think marriage is an out-dated institution, versus a quarter of Britons and a third of the French.
Of course, they are facing a demographic crisis of falling birthrates, and we aren't.