“It’s like a husband being upset that their ex-wife went off and had a cup of coffee with some other man.”

It was a nice line from Treasurer Joe Hockey on Radio National this morning, speaking about Labor’s reaction to a deal struck by the Coalition with the Greens to scrap Australia’s debt ceiling.

It is just a coffee, after all, not the illicit affair Labor had with the minor party for the last three years. And for the Greens, it’s a rare bit of economic sense — most economists will tell you Australia doesn’t need a ceiling on debt levels, and we certainly don’t need the sort of bitter brinkmanship seen in America’s Congress on the issue. Greens leader Christine Milne successfully negotiated the right outcome.

The base might scream at Milne — a less electorally popular leader than her predecessor who’s on reasonably shaky ground after a poor performance in the September poll — for doing deals with Abbott. But if the Greens are fair dinkum about playing politics in the new Tony Abbott-led world, they need to work with the government on issues they care about and not just knee-jerk against them.

The marriage is over. The Greens must play the field a little.