Amid the furore of a presidential impeachment scandal back home, US secretary of state Mike Pompeo inaugurated “a new era” in relations with Greece, the country increasingly seen as a pillar of stability in an ever more turbulent region.

At least physically several thousand miles away from the hurly burly of the impeachment inquiry against Donald Trump in Washington, which has drawn in senior administration players including Pompeo, the secretary of state indulged in a rare charm offensive at the weekend.

The Trump administration went out of its way to upgrade ties with the Nato member state. “I have come to Greece to expand the partnership that’s already at the best level it has ever been,” Pompeo said after signing a revised mutual defence cooperation agreement.

“A strong and prosperous Greece is good for the Greek people and good for America,” he added in a tweet late Saturday.

The two–day visit, which ended Sunday with Pompeo touring archaeological sites in the heart of ancient Athens, was the last in a four-nation European tour largely dogged by the Ukraine-US debacle.

But few official stopovers have been as crucial. With US diplomats placing renewed focus on the energy-rich eastern Mediterranean – an area they readily admit has been vastly overlooked, allowing “malign actors” to compete for power – Greece, geopolitically, has attained a new status as a key partner on Europe’s strategic southern flank.

“We are opening a new chapter in our history,” the prime minister, Kyriakos Mitsotakis, told Pompeo. “Our relationship has truly never been as strong as today.”

No US secretary of state has spent as much time in Greece in years.

The trip partly reflects the cooling in ties with Ankara under the unpredictable stewardship of president Recep Tayyip Erdoğan. Talk of the US removing military installations from Turkey has been muted. Greek-US relations have warmed as tensions have risen in the eastern Mediterranean between Cyprus and Turkey over offshore gas rights.

But in substance, as much as feel, analysts say Pompeo’s tour also highlights the choice the Orthodox nation has made to align its interests with Washington at a time when Greece, Cyprus and Israel have also formed a tripartite energy alliance, to the delight of the Trump White House.

“The time when many Greeks wanted to minimise the US military footprint in their country is well and truly over,” said international relations professor Aristotle Tziampiris at the University of Piraeus. “What we are witnessing is a dramatic improvement in ties especially on the military, energy and political fronts. For Greek standards this is happening at the speed of light.”

In a society where anti-Americanism has never been far from the surface, it is a choice that has been all the more extraordinary for its cross-party embrace.

Mitsotakis’ centre right government is to a great degree building on the legacy of his leftist predecessor Alexis Tsipras. In office until July, Tsipras actively sought to promote bilateral links despite opposition from cadres who had not forgotten US support of authoritarian governments following the country’s bloody 1946-49 civil war and Washington’s backing of the ruthless military regime that ruled between 1967-74.

Indicative of that sentiment, diehard leftists protested in Athens Saturday deploring a defense accord that will see US bases expand across Greece and vigorously chanting: “Americans, Murderers of the People.”

Technical teams fly in this week to put the final touches to the open-ended military agreement, one that will allow the US to further expand a deep-water naval base used by the Sixth Fleet on Crete, create facilities for helicopter pilots and bases for drones. As part of the pact, Greek armed forces hit by steep budget cuts during the country’s long-running debt crisis, will also benefit.

The upgrading of ties will also see US influence expand in both the economic and energy sectors, where Washington is keen to upgrade Greece’s role as a regional supply hub of natural gas. “After years of taking the eastern Mediterranean for granted, the United States has stepped back to take a considered, whole-of –government look at how we advance US interests and build peace and prosperity in this crucial region,” the US ambassador to Greece, Geoffrey Pyatt, said last week. “Together with Greece and other democratic partners, we are working to push back on malign actors like Russia, China and Iran [that] have different interests and values and different visions for the future of this region.”

Before arriving in Athens on Friday, Pompeo visited the Balkan states of Montenegro and North Macedonia. Moscow’s meddling in the area – one it has long viewed as falling within its own orbit – assumed brazen overtones last year when it tried to thwart resolution of the decades-long name dispute between Skopje and Athens in a bid to stop Macedonia joining Nato.

Despite once warm relations with the Kremlin, the Tsipras government pushed through the deal.

Under the new military accord, the US will invest heavily in setting up a new naval and air force base in Alexandroupolis, which is also emerging as a regional energy centre with plans to supply US liquid natural gas to southeastern Europe via the emerging regional pipeline network. Russia had also expressed interest in developing the Aegean port.

“Alexandropoulis symbolises the new Greek-American commercial and military relationship,” said professor Tziampiris. “Ten years ago none of this would have been feasible.”