(Bloomberg Opinion) -- Many things divide the 27 member states of the European Union these days, but one controversy in particular sums up the bloc’s fundamental dilemma. It's over “enlargement,” and specifically whether to formally start accession talks with North Macedonia and Albania. Seething below the surface is the question of whether the EU can, in Eurocrat jargon, keep “widening” and “deepening” at the same time.

Put differently, if the EU keeps admitting new members, whether they’re ready or not, won’t it just become ungovernable and drift apart?

As usual, it fell to French President Emmanuel Macron, who’s earned himself quite a reputation for being undiplomatically honest, to point out this tension. He shocked other EU leaders by blocking formal talks with North Macedonia and also, supported only by Denmark and the Netherlands, Albania. German Chancellor Angela Merkel, among others, was irate; the Balkans were livid. The EU is now scrambling to get him to drop his veto before the European Summit in March.

Two main arguments were hurled at Macron. First, that he was being unfair in failing to recognize how much the two countries have already done to become good candidates. Albania has cleaned up its judiciary and cracked down on organized crime. The other country even changed its name (adding “North”), just to appease EU member Greece, which has a region that argued it had dibs on “Macedonia.” The EU had promised that this would be enough to start negotiating.

Second, Macron was accused of being strategically myopic, just when the EU needs to start thinking “geopolitically.” Russia and China are already extending their tentacles into south-eastern Europe, the latter by financing ports, bridges and rail lines as part of opaque political deals. If the Balkans feel spurned by the EU, they’ll run, rather than walk, into the arms of non-Western autocrats.

All true. But there’s also a good reason for objecting to enlargement: It inevitably gums up integration between the EU’s existing members. Working together was hard enough among the six founding countries back in the 1950s. With each new entrant, it kept getting harder yet, as new languages, political cultures, historical grievances and national interests had to be accommodated. This was true after the U.K. joined in 1973 (and look where that led) and after the Mediterranean and Nordic expansions later.

The dilemma became especially clear after the two eastward expansions in 2004 and 2007. The same arguments were being used then as now: Not admitting the post-communist nations would have been geopolitical folly, stranding them in the sphere of influence of their former Russian oppressors. And it would have been unfair to people who had long and valiantly struggled for their freedom and yearned to join “the West.”

More than a decade on, however, and some of those eastern members have turned into spoilers of the European project, or worse. Hungary is a quasi-autocracy that proudly calls itself “illiberal.” Poland is actively undermining the independence of its judges and the rule of law, in open confrontation with the European Court in Luxembourg. Both are obstructing any progress in formulating a common European policy for dealing with migrants. In effect, they have rejected the EU’s founding idea of European solidarity in favor of an atavistic nationalism.

Each previous round of enlargement thus introduced new fractures into the EU, some between north and south, others between east and west. Macron is hardly alone in observing that European integration stalled long ago, and that “widening” had something to do with that. In foreign and defense policy, any member state can veto any decision, thus assuring European irrelevance and impotence on the world stage. Bigger ideas like a European army are nothing more than pipe dreams. In the euro area, neither banking nor fiscal union has been completed, thus leaving the currency union prone to another crisis.

All of this is part of thinking geopolitically. Without a euro to rival the dollar, without diplomats or soldiers that Turkey, Russia, China and others take seriously, what good will the EU be in the long run?

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