Nato's top commander in Europe, US Gen James Jones, has been meeting officials in Romania and Bulgaria, exploring possible future military bases for US forces in the Balkans.
Washington plans to redeploy large forces in Europe
He says such strategically-positioned bases would enhance Nato's capabilities as the US adjusts its post-Cold War priorities.
The BBC's South-East Europe analyst, Gabriel Partos, examines the US plans.
The commander of United States forces in Europe, Gen James Jones, has been inspecting military sites in Bulgaria which the US might use in future as bases when it redeploys troops from western Europe.
Gen Jones' visit, and a series of talks in Romania, come as part of his preparations for Congressional hearings at which he will outline the Pentagon's plans for reassigning US forces in Europe.
Washington is planning to withdraw from their current locations some 70,000 troops stationed abroad.
Most of the forces to be redeployed - including two heavy army divisions based in Germany - are to be pulled out of western Europe.
Notwithstanding the reductions in US strength in western Europe over the past 15 years, the continuing presence of troops there in substantial numbers is seen as part of the Cold War's now redundant legacy.
Gen Jones has already visited several sites in Bulgaria
In that bygone era, the troops' primary role was to resist a possible Soviet conventional attack.
Today's security environment is very different.
Washington perceives many of the main threats to its interests as coming from the Middle East - a volatile, oil-rich region which is either the source of, or the stage for, a number of conflicts.
During the Iraq war, the US made use of military bases in Bulgaria and Romania to assist its military effort.
These two south-east European countries are much closer to the actual and potential trouble-spots of the Middle East than Germany.
They are also in close proximity to Kosovo, home to the largest remaining US base in the region, and to Bosnia-Hercegovina.
The threat, even if remote, of a potential flare-up in either of these two areas means that swift reinforcements might be required.
Bulgaria and Romania also offer other benefits for the Pentagon - not the least of which is the fact that costs are considerably lower than in western Europe.
However, as the US administration has made clear, there is no question of any large-scale redeployment of US troops in south-eastern - or for that matter, central - Europe.
Most of the troops to be pulled out of Germany will be returning to the US, or they will be deployed in various trouble-spots elsewhere, as and when they are required.
That means that Washington's plan for the new military facilities envisages the deployment of small units, mostly maintenance and logistical staff, who can handle at short notice much larger troop movements in times of emergency.
Some may also be used for training purposes and for military exercises.
But as Gen Jones made it clear during his visit to Bulgaria, the four or five facilities the Pentagon is seeking there will not be US bases in the traditional sense of the term:
"The type of facilities that we hope to be able to partner with Bulgaria will affect the US navy, the US air force, US army, the US marines, and hopefully some facilities where we can pre-position equipment," Gen Jones said.
"We are not talking about establishing US bases. This is a partnership arrangement where these will be Bulgarian bases, at which we will be privileged to be a tenant."
Yet whatever the limitations of these plans, Bulgaria and Romania - as well as other countries in the region - are eager to attract a US military presence.
A continuing US deployment would be seen as consolidation of the host countries' integration in the Nato security system.
Direct financial benefits linked to the US presence are among some of the important considerations.
And there are also likely to be indirect benefits with a possible expansion in foreign - particularly American - investment.
That is because some investors regard a US military presence in a country as a sign of stability.
Whatever the advantages, and possible drawbacks, the process of US redeployment is a lengthy one.
According to current plans, it is unlikely to get under way until next year.