A clever politician chooses their battles carefully. Because even the most brilliant minister can never achieve everything they want, the trick is to focus your attention on areas where you can show real, tangible results.
The kindest thing you can say about the Greens after two and a half years in government is that they are not very clever politicians.
Time after time, John Gormley and his colleagues have gone out on a limb in battles where they are ultimately doomed to humiliating defeat. To compensate for this they've insisted on pushing through other policies that nobody except their core voters (who make up around 3pc of the population) actually want.
It would almost be possible to feel sorry for them -- except that when it comes to picking up the tab for their political naivety, it's the public who are the real losers.
Recent events show why the Green experiment is one that the electorate will almost certainly not want to repeat at the next General Election.
After less than a week, it's already clear that the 30kph speed limit in Dublin city centre is a dismal failure, the sort of crackpot scheme dreamt up by people who've never actually had to get behind the wheel of a car.
Meanwhile, Gormley seems powerless to prevent a 600,000- tonne incinerator on the Poolbeg peninsula that nobody wants -- the one area where you might have thought a Green minister would actually be able to achieve something.
Make no mistake, Dublin's new snail-paced speed limit is a Green idea pure and simple. It's all part of a misguided campaign to make life miserable for the motorist, in the hope that they will hop on a bike instead. Presumably this is also the justification for a new €10m city centre cycle track voted through this week, which at 4.6km works out at a trifling €570 per foot.
What some Greens can't seem to understand, however, is that Dublin is not Amsterdam. For the majority of commuters who have to travel significant distances to their workplaces, the bicycle is simply not a realistic option -- and while bringing the city to a standstill may make some environmentalists feel more virtuous, the new go-slow limit is really just a fig leaf to cover up the Greens' embarrassing failure to secure more funding for public transport.
The Poolbeg row is in a completely different category. The Minister for the Environment and Dublin City Council are now locked in an almighty row over the issue, with city manager John Tierney taking the unprecedented step of paying almost €125,000 for an ESRI report that completely rubbishes Gormley's waste policies.
The Green leader, in turn, has accused the council of economic illiteracy and complained that they're muscling in on his territory. Here, at least, Gormley is on the side of the angels. The folly of Poolbeg has been confirmed by the revelation that Covanta Energy are already in discussions with waste producers outside Dublin to supply it with enough rubbish to fill the facility.
This is sheer madness -- but with the contract signed and almost €60m spent, unless Gormley has some cunning plan up his sleeve it appears that he is ultimately powerless to prevent it from going ahead.
Sadly, this is all part of a pattern that the Greens in government have made their own -- a lot of big talk, not a lot to show for it. They insisted on a public banking inquiry, then backed off like mice when Brian Cowen announced a private one. Eamon Ryan spent last weekend on the airwaves promising a bailout for mortgage holders that has now been put firmly on the backburner.
There's supposed to be an election for Dublin mayor in June, but most government insiders believe that Gormley has dithered too long and that the vote will have to be postponed.
The Greens have failed to choose their battles carefully. That's why they look set to lose their long-term political war.