PARIS — In this era of illiberal authoritarianism, Emmanuel Macron is trademarking a paradoxical brand: the liberal strongman.

The young, centrist French president, flush with electoral successes that have wiped out the old political class and given him an absolute majority in parliament, is taking full advantage of the Fifth Republic constitution, made to measure for General Charles de Gaulle, to consolidate his power.

With bone-crunching handshakes and plain speaking, he seems determined to show himself as much the alpha male on the global stage as Donald Trump, Vladimir Putin or Recep Tayyip Erdoğan, but in the cause of liberal values — multilateral governance, open trade, human rights and diversity — that make him the antithesis of their nationalist ideologies.

At home, Macron has displayed ruthless opportunism. In just six weeks in office, he has split and decimated the main political parties, turned his own fledgling movement into the biggest political force in the country, upstaged his own center-right prime minister, Edouard Philippe, and eased his main centrist ally, François Bayrou, out of government over a party funding scandal. He has humiliated Manuel Valls, the former Socialist premier under whom he served, imposed new rules of the game on the media and moved to entrench emergency search and arrest powers permanently, on grounds of national security.

The 39-year-old political novice has forced political old-timers to kiss his ring or face electoral oblivion. His advance from stripling to strongman belies his youth and relative inexperience.

At some point, the new French president's taste for personal power and his libertarian instincts are likely to collide.

De Gaulle had the aura of a war hero turned national savior and statesman who returned to power in 1958 at age 67 to “rescue” France from the revolving-door governments of an unstable parliamentary system. Macron has accrued similar powers after serving only as a presidential adviser and briefly as economy minister, and never before holding elected office.

He is determined to carry out a “Jupiterian presidency,” a reference to the king of the gods in Roman mythology. The term evokes a leader who sets a long-term course, speaks only occasionally in public and stays aloof from daily affairs. It is an intentional contrast with his predecessors, Nicolas Sarkozy and François Hollande, who gave a running commentary in the media on daily events, micro-managed government and party business, but were unable to enact a strategic plan to reform the country.

Macron’s role models are De Gaulle and Francois Mitterrand, each of whom had grand, long-term objectives — decolonization and modernization for the former, social justice and European integration for the latter — that enabled France to punch above its weight on the world stage. Macron's objectives are a fusion of theirs: economic reform and European integration.

The new French leader’s critics say he is already showing signs of succumbing to the foibles of personal rule: an over-concentration of power, a tendency to sideline intermediate institutions such as trade unions and political parties and a demagogic use of the symbols of power. His long, slow walk through the courtyard of the Louvre Palace on the night of his presidential election triumph and his early use of the ornate Versailles Palace — home of the “Sun King” Louis XIV — to host Russian President Vladimir Putin illustrated his taste for harnessing the trappings of state to project personal authority.

Macron plans to use Versailles again on Monday as the backdrop for a rare solemn address to a congress of both houses of parliament, which last met in November 2015 when Hollande declared that France was at war with terrorism after terrorist gunmen killed more than 100 people in the Paris region.

Macron’s style carries echoes of the overmighty “imperial presidency” in the United States criticized in Arthur M. Schlesinger Jr.'s 1973 seminal book. The historian of the White House showed how Franklin D. Roosevelt built up the executive office, augmented its staff and took greater control over a range of government agencies created during the New Deal and World War II, on which subsequent presidents built to expand their power.

In the U.S., the president wields broad executive powers as commander-in-chief and head of state of the most powerful nation on earth. But his domestic authority is subject to a series of checks and balances — Congress, the courts, watchdog agencies and the media — which have combined to challenge and thwart presidential overreach in the first months of Trump’s erratic rule.

French presidents, especially when they have a cohesive parliamentary majority, face fewer constraints and a weaker, more supine media. The absence of political or judicial counterweights carries its own dangers. It can lead to abuses such as Mitterrand’s use of wire-tapping to shield his double private life, or Sarkozy’s flouting of campaign spending limits, which might never have led to prosecutions if he had been reelected in 2012.

French presidents, especially when they have a cohesive parliamentary majority, face fewer constraints and a weaker, more supine media.

It can also lead to opposition shifting to the streets. Successive French rulers, including De Gaulle, faced mass protests that forced them to change course, abandon reforms or offer concessions. Macron is likely to face such a challenge later this year to his planned decrees to loosen labor market regulation.

At some point, the new French president's taste for personal power and his libertarian instincts are likely to collide.

The Macron paradox is that his avowed aim is to decentralize some of the very powers he has gathered into his hands. The homeland of Montesquieu — the 18th-century political philosopher who developed the idea of the separation of powers — has a strong executive, a weak legislature and an under-resourced judiciary prone to government influence.

The new president wants parliament to spend less time rubber-stamping laws and more time scrutinizing the work of government. He has pledged to strengthen the independence of the judiciary and moralize public life. Furthermore, Macron envisages ceding some budgetary sovereignty to a future eurozone finance minister, although he has yet to flesh out his proposals.

Each step would arguably strengthen France. But it would also indubitably dilute the president's power, and make taking the next step all the more difficult. Macron is likely to find that the real test of a liberal strongman is whether he can stay liberal when the going gets rough.

Paul Taylor, a contributing editor at POLITICO, writes the Europe At Large column.