In a democracy, 50% support doesn't give leadership much clout.
Ask US President George W. Bush. In last year's election he lost the popular vote and barely won the electoral vote. He finds himself haunted by questions about the legitimacy of his leadership. To make matters worse for him, Congress is evenly divided as well.
By standards of the US presidency, Bush's position is weak. He knows it. He treads carefully.
And he finds himself at absolute loggerheads with the European Union.
As he departed for the second European visit of his brief presidency this week, reminders appeared everywhere of deep and widening disagreements between the US and Europe, large among them missile defense and-of course-the Kyoto Protocol on Climate Change.
There is little doubt that for Bush and, by extension, the US, the antagonist is not so much Europe as it is the EU.
On missile defense, the EU bludgeons US concern for its own security with rigid support of an obsolete treaty.
And on Kyoto, group members-amazingly-are appalled that Bush made clear his country's sensible intention not to ratify a treaty that would cost so much and achieve so little.
The EU's leaders thus behave as though pointless compromise of national interest is the only route to international acceptance-in which case, who needs international acceptance?
A festering sore in all this is the EU's scuttling of General Electric's plan to merge Honeywell. American courts had approved the deal, finding it wouldn't hurt consumers. But the EU's European Commission blocked it, finding it would inconvenience GE's competitors, many of them European.
This is a government body acting not only within its jurisdiction but also internationally in a manner no one would describe as careful. This is a supranational government supremely confident about the legitimacy of its circumstance.
And this is a government body with popular approval no more compelling than the hair-thin electoral margin with which Bush must struggle.
Twice a year, the EU conducts a poll called the Eurobarometer to gauge Europeans' approval of its work. On the basic question whether Europeans think their countries benefit from membership, the EU in recent years has seldom scored much above 50% affirmation.
And the most recent Eurobarometer survey, conducted in April and May and reported this week, showed an approval decline.
Of Europeans surveyed, only 48% said they consider EU membership to be beneficial to their countries. The share compared with 50% in the previous poll, conducted last November and December.
This spring's survey noted sharp approval declines in Belgium, the Netherlands, and Luxembourg, founding members of the European Economic Community, the EU's precursor, and usually strong supporters of membership.
Most approval indicators in the spring survey were down. An exception concerned the euro, support for which rose by 4 percentage points to 59%.
To be sure, a survey is not the same as a vote. But the only part of the EU that directly represents Europeans is the EU Parliament, which acts mainly on budgetary matters and legislation from the Council of Ministers.
So the Eurobarometer represents an important test of EU legitimacy. By that measure, the group wobbles on shaky ground: less than 50% support, worse than Bush.
Yet the EU's leaders don't tread as carefully as Bush must. They're not accountable to voters to the extent he is. And they increasingly assert power despite an eroding base of popular support.
A growing willingness to export aggressive governance as consent of the governed fades should worry the rest of the world.