PARIS — Emmanuel Macron's rise to power is rekindling the Franco-German relationship — at least on the surface.

When Angela Merkel gave her support for plans to develop a European fighter jet in Paris last week, France's president hailed a "profound revolution" in their cooperation — never mind that costs, delivery times and potential developers for the jet are as yet unknown.

That project, just like plans to boost French and German language training in each other's countries, underscores the eagerness to highlight Franco-German initiatives. Merkel has endorsed, albeit in the broadest possible terms, Macron's calls for deeper eurozone integration, complete with a budget and finance minister.

But while goodwill abounds — one French diplomat told a local paper that "everyone is overflowing with ideas" — the cheerful mood does not amount to a revolution. Serious hangups remain when it comes to the German trade surplus, French reform credibility, solidarity between EU countries, bailouts and defense spending, among other topics.

And while Macron's election has unleashed enthusiasm in Paris and Berlin, Germany has its own vote coming up. If Merkel wins in September, and it's very likely she will, and forms a coalition with the Social Democrats, there will be pressure to hold down defense spending and cooperation. If she rules with the Greens and liberal Free Democrats, there could be fierce resistance to the eurozone budget and finance minister plan.

Here's a rundown of key points of tension between France and Germany.

1. Germany's trade and current account surplus

Macron, like U.S. President Donald Trump, is a frequent critic of German trade and current account surplus, which he's termed "unacceptable." In April, before his election, he told regional daily Ouest France that Germany's situation was "not tenable over time." In July, speaking to the same paper but this time from the Elysée, he said "part of German competitiveness" was down to eurozone "dysfunction" and the "weakness of other economies."

Berlin has taken such criticisms on board — to a degree. In May, Finance Minister Wolfgang Schäuble told Der Spiegel that his country's current account surplus — over 8 percent of gross domestic product — was "too high."

But when it comes to solutions, Paris and Berlin remain poles apart. Macron wants Germany to start steering its surpluses toward Southern Europe, essentially setting up an EU transfer union. Schäuble told Der Spiegel any such move would have to be approved by German voters, a roundabout way of saying it's unlikely to happen.

Jens Weidmann, head of the Bundesbank, was far harsher when he told Welt am Sonntag last month he didn't "see any reason why Italy should co-finance bridges in Germany, or why Portugal should fund sections of the German motorway or vice-versa."

2. German defense spending, or lack thereof

Spending on the military, and willingness to engage in dangerous combat operations, is another area of profound divergence.

Macron used Trump's visit to Paris on July 14, and the military pageant that day, to underscore just how different France is from Germany from a military standpoint. The French president has pledged to boost defense spending to 2 percent of GDP, in line with a NATO target, by 2025, despite a controversial €850 million spending cut this year. Merkel has also promised to hit the NATO target, but without saying when.

In his Ouest France interview, Macron stated it was "not up to him" to decide whether Germany should boost defense spending, but that the world was becoming increasingly dangerous and it was "naïve" to keep living under "someone else's umbrella."

France may be happy to remain Europe's biggest military power in post-Brexit Europe, but ramping up military cooperation would, ideally, involve greater German involvement via increased spending and more active participation in combat roles as part of EU units. What Macron may be less comfortable with, however, is that with or without Merkel in the chancellery, the Germans will likely meet the 2 percent spending target at some point — and that would make Berlin the largest spender on defense in the EU.

3. Macron's ability to reform

Since Macron swept to power and secured a commanding majority in parliament, it's become less fashionable in Germany to express doubts about France's ability to reform.

The new president is pressing ahead with plans to overhaul labor rules by the end of September. If he can loosen hiring and firing rules, overhaul a deeply indebted unemployment benefit system and stick to deficit-reduction targets, he will effectively have robbed Germany of a major excuse not to press ahead with eurozone reform plans.

But German skepticism about France and its ability to conduct unpopular reforms isn't going away.

Schäuble said in May that his attitude toward Macron was one of "respect and reserve" and Germany is in no rush to grant France a clean bill of health on its economy, which is blighted by high unemployment, weak growth and heavy indebtedness.

Berlin is also waiting to see how Macron — whom Der Spiegel dubbed "the expensive friend" — fares in September when far-left leader Jean-Luc Mélenchon, flanked by hard-line trade unionists and a broad church of Macron opponents, takes to the streets to protest against what he has called the "destruction, pure and simple" of France's labor protections.

It will take more than goodwill from Macron to convince Germany that France is a changed nation, ready to be lean and mean in a globalized economy. What's more, just as France finds comfort in its status as a military power, Germany derives benefit from being Europe's economic power. Declaring France a suitable partner for reform will not be easy.

4. The path to eurozone integration

During his campaign for president, Macron's calls for a eurozone budget and finance minister were met with silence in Berlin. Now that he's in power, Merkel said Germany could "naturally think of a common finance minister if conditions are present." The final four words are the important ones, as they sum up the differences between France and Germany on eurozone integration.

As Schäuble told Spiegel in May, a eurozone finance minister would require a budget, and to set one up there would need to be a change in the EU treaties. While Merkel and Macron said in June that treaty change was "no longer taboo," it's not being pushed in the German chancellor's campaign for reelection.

Depending on who ends up in Merkel's ruling coalition — assuming she wins — attitudes toward treaty change and the contours of eurozone reforms would differ greatly. In May, the Social Democrats' Sigmar Gabriel voiced cautious support for Macron's ideas in a document titled "Elysee 2.0: New Impulses for German-French Cooperation."

But if Merkel splits with the SPD and joins forces with the FDP and Greens, then the balance will shift toward conservative positions unfriendly to treaty change.

Schäuble indicated in his May interview that he was supportive of expanding the functions of the European Stability Mechanism, the eurozone's permanent bailout fund, which, crucially, is not subject to democratic control. Weidmann rejected all of Macron's notions when he spoke to Welt Am Sonntag in June, arguing existing structures could accommodate all the integration that Europe needed.

5. Battle for control over the ECB

Macron's indictment of eurozone imbalances carries an implicit criticism of the European Central Bank, which, despite spending billions to boost inflation, has failed to do just that — with low inflation favoring the export-led German economy.

The reign of Mario Draghi, who enforced a loose monetary policy that drew a line under years of sovereign debt crisis, was a step in France's direction, and one that irritated the Bundesbank's inflation hawks. But in 2019, Draghi's term expires — and getting the ECB job is on Berlin’s wish list. That's because if Merkel is to agree to a common eurozone budget or investment fund, she will need a big concession from other EU members in order to sell it to her own party and the German people.

At a time when eurozone growth is starting to accelerate, with the bloc's economy growing by 1.9 percent year-on-year in the first quarter, a slowdown two or three years from now could douse French enthusiasm for eurozone reform and revive populist embers still smoldering after the presidential campaign.

France is yet to begin public jockeying for the position, but as Draghi's end date draws near, control over the ECB is sure to loom powerfully as a subject of debate between Paris and Berlin.