The United States is set to unveil a Black Sea package, adding more warships and surveillance in the old Cold War arena on the 70th anniversary of the North Atlantic Treaty Organisation (Nato), the backbone of the Western alliance.
The three-day occasion in Washington, gathering the foreign ministers of 29 Nato members, is laden with ceremony and symbolism.
Yesterday, Nato secretary-general Jens Stoltenberg was slotted to address the joint chambers of Congress - the first time the head of Nato has been invited to do so.
Another event was to be held in the Mellon Auditorium, where then President Harry S. Truman had hosted the signing of the North Atlantic Treaty in 1949.
The message will be one of unity and reassurance. But behind the bubbly, there will also be some serious business. At 70, Nato is gearing up for a new phase - countering a revisionist old enemy, Russia; and containing a rising power, China.
Nato also faces the challenge of a US-led exit from the 17-year war in Afghanistan without allowing space for radical groups to gain traction there.
President Donald Trump has triggered unease over the degree of US commitment to Nato. His escalating demands that Nato partners pay their fair share of defence costs has put pressure on members such as Germany and Italy.
"The Trump administration is ruthlessly transactional and disregards the normal diplomatic route for doing things," Mr Jacob Parakilas, deputy head of the US and the Americas Programme at London think-tank Chatham House, told Al Jazeera.
Mr Trump has been somewhat successful.
Since 2016, Nato members have stepped up their spending by US$40 billion (S$54 billion), Mr Stoltenberg said on Tuesday.
Earlier, a senior US State Department official told journalists: "We anticipate there will be, by the end of 2020, more than US$100 billion in additional new spending from our allies on defence."
Despite the unease, Mr Trump has strengthened the alliance by sending a signal to Europe that it needs to step up to its own defence rather than rely on the US to do the heavy lifting.
"Trump has - not by intention, but inadvertently - done Europe a big favour," Mr Robert A. Manning, senior fellow with the Scowcroft Centre for Strategy and Security at the Atlantic Council, told The Straits Times.
Nato and the European Union had been forced to "see an urgency in the Euros getting their act together in terms of the EU's future, economic competitiveness and European security, without America, or despite America", he said.
Mr Manning added: "Trump has accelerated the European hedging strategy across the board. Defending the status quo and trying to roll back Russia in Ukraine is a serious mission, one the Euros now know requires serious defence capabilities."
The Black Sea package "beefs up the surveillance, both air surveillance as well as more of the Nato country ships going into the Black Sea to assure that there is safe passage from Ukrainian vessels through the Kerch Straits, the Sea of Azov," ambassador Kay Bailey Hutchison, US Permanent Representative to Nato, said on Tuesday.
"It is very important... that the countries in and around the Black Sea are safe from Russian meddling," she said. "Russia is putting defensive weapons in Crimea. Crimea is part of Ukraine. And it is very important that Romania, Bulgaria and Ukraine, as well as Georgia, have the security in that Black Sea area both for ships, but also for their land-based safety."
Nato is also assessing what China is doing, Ms Hutchison added.
Just days ago, Italy raised eyebrows when it became the first Group of Seven member to embrace China's Belt and Road Initiative (BRI) - Chinese investors signed 29 separate deals amounting to US$2.8 billion worth of projects.
"China is buying rights into seaports in Italy as well as in other parts of the world. They're getting very active in container port investment," Ms Hutchison said.
"We are also very concerned about the 5G networks that Chinese companies have the capability to deliver but also, because of Chinese law, have a responsibility.
"If the Chinese government asks for information that is proprietary, they would be required to give that to the Chinese government, which is of concern to Nato countries because we want to make sure our communications systems are secure.
"So if a country is investing in the 5G infrastructure that could interrupt Nato communications, or again, have our Nato communications be distorted or disrupted, that is a very serious issue for Nato. We are assessing risk. We're much more active in doing so with China."
But she added: "We don't consider China an adversary. We want to have free and fair trade with China."
Asked if the US was committed to Nato, Ms Hutchison said: "Yes, absolutely.
"In our goals of our command structure, we have a goal of four 30s - 30 air squadrons, 30 battalions, 30 warships, in 30 days, anywhere in our alliance that they need to be.
"That is the goal of deterrence so we can meet any challenge that might come to any of our countries, and America is committed to that."