U.S. Sen. Daniel Inouye on Tuesday gave his home state its first heads-up on the big news: The U.S. Department of Defense intends to move more than 2,500 of its personnel from Japan to Hawaii, after paring back what had been a $21.1 billion military ramp-up in Guam.

The Pentagon has worked on this since 2006, when a pact was struck with Japan to relocate 8,600 Marines and 9,000 dependents from Okinawa.

Defense chiefs confirmed the Hawaii numbers on Thursday, also clarifying that up to 5,000 of the Marines are still bound for Guam.

It makes sense from a federal fiscal perspective: A larger presence in Guam would have required a costlier buildout there, in a lean time when the Obama administration is trying to curtail military spending where it can.

The move must be read by Hawaii officials as excellent news. The Marines and their dependents will need housing, and construction — as well as the spending by the new Hawaii households — will give the islands’ building industries, and the overall economy, a needed boost.

Congress still must approve the proposal, but a fair measure of delay also should be greeted with a sigh of relief. Inouye underscored the clear reality that "there is a lot of work that needs to be done to prepare for their arrival."

In addition to the housing, more training areas will be needed, as well as various improvements to infrastructure.

There are also broader impacts to consider. The pressure on the local rental market, for example, is among the leading concerns.

Based on the count of the Okinawa-based contingent, the group coming to Hawaii could number around 5,000, including dependents.

Military officials say the Kaneohe’s Marine Corps Base Hawaii is the preferred location for the troops, but the area already will be crowded with other planned force realignments.

There are, for example, proposals for Navy P-8A Poseidon jets, Osprey tilt-rotor aircraft and new attack, utility and heavy transport helicopters — adding up to a 49 percent increase in airfield use by 2018. That, officials say, might make it impossible to base all the Marines there.

It would be better for the Oahu community to scatter the impact a bit. Otherwise, a concentrated influx in one area would have the potential to drive up rents for everyone, because military families would be given a housing allowance that puts higher rents within their range.

Using the Defense online calculator for the Basic Allowance for Housing (BAH) (www.defensetravel.dod.mil/site/bahCalc.cfm) makes the point.

The BAH varies according to local market conditions; entering the Kaneohe ZIP code gives an allowance of $1,451 without dependents for the lowest rank (E-1), $1,860 with dependents.

Communities surrounding military bases have observed rental spikes in the past, and it’s always a fresh reminder of how critically Hawaii needs affordable options for renters.

Beyond housing, government planners should keep tabs of anticipated increases in military arrivals to ensure that the entire range of social infrastructure — schools, utilities, roads — accounts for them.

On islands sensitive to crowding, accommodations for this growth must find a balance that the entire population can live with.

The U.S. defense posture is shifting inexorably toward the Asia-Pacific zone, and Hawaii sits in the middle. The military will become an increasingly critical part of the islands’ community.

Inouye expressed confidence "that the people of Hawaii will welcome these brave men and women and their families with aloha."

Most people will surely embrace that sentiment, with the expectation that their government will proceed with everyone’s welfare in mind.