I need help finding a book.
The title is an Acronym I believe 4-5 characters separated by periods.

I read the first book as a child and want to read the rest of the
series for nostalgia. The book in question was paperback when I read
it.

The premise of the book is someone explodes a nuke somewhere in the
west (Arizona?) and thus starts the war.
The US was developing mech suits that had the capability of "jumping"
over a mile (think Incredible Hulk movie). These suits fire balls of
explosive material from an arm launcher (c4 maybe).

The main character finds something amiss and tells his "girlfriend or
wife" to get out and move out to the bomb shelter they had made. Luck
had it that she restocked it recently (coincidence I know) because she
took her schoolchildren (she is a teacher) to the "bunker" recently.

All in all the mech suits were deployed for some reason and they march
to stop "the Russians" (if I recall correctly) in Washington (someone
dropped a neutron bomb over the area).

/sigh.. This one is a doozie..

I believe your series is C.A.D.S. (an acronym for "Computerized
Attack/Defense System), by John Sievert (a pseudonym).

"They're called C.A.D.S.- Computerized Attack/Defense System.The next
generation of America's high-tech soldier. Seven foot tall battle
armor suits that are equipped with flame-throwers, armor piercing
shells, machine guns and much more.all operated by voice command.
However no one dreamed that they would become America's last line of
defense. The unthinkable has happened. The Soviet Union's nuclear
first strike has left America crippled, tens of millions dead, and its
armed forces decimated. Now the Soviets begin their sweep across the
American landscape to achieve complete victory. Only one thing stands
in their way: Colonel Dean Sturgis and his C.A.D.S. unit. Now,
untested in battle, the C.A.D.S. must race against time to rescue the
President from his White House bunker before the Soviet's can capture
him and demand the surrender of the United States."

Thrift Books: C.A.D.S.
http://www.thriftbooks.com/viewDetails.aspx?ISBN=0821716417

Some of the C.A.D.S. books are available used:

AddAll Rare, Used and Out of Print Book Search
http://used.addall.com/SuperRare/RefineRare.fcgi?id=060817192031799868 

Here's a list of the C.A.D.S. titles and the actual authors' names:

"SIEVERT, JOHN; house pseudonym 
C.A.D.S. [by Ryder Syvertsen & Jan Stacy] (Zebra 0-8217-1641-7, Nov
?85, $3.50, 398pp, pb) [C.A.D.S.] Sf war novel of the ?Computerized
Attack/Defense System?. They are the ?high-tech soldiers of tomorrow,
fighting for America?s survival.?
C.A.D.S. # 2: Tech Battleground [by Ryder Syvertsen] (Zebra
0-8217-1790-1, Apr ?86, $2.95, 285pp, pb) [C.A.D.S.] Sf post-holocaust
adventure novel of armored warriors vs. Soviet invaders, second in the
series.
C.A.D.S. # 3: Tech Commando [by Ryder Syvertsen] (Zebra 0-8217-1893-2,
Sep ?86 [Aug ?86], $2.95, 252pp, pb) [C.A.D.S.] Post-holocause sf
series adventure novel.
C.A.D.S. # 4: Tech Strike Force [by Ryder Syvertsen] (Zebra
0-8217-1993-9, Feb ?87 [Jan ?87], $2.95, 270pp, pb) [C.A.D.S.] Fourth
novel in the sf post-holocaust adventure series.
C.A.D.S. # 5: Tech Satan [by Ryder Syvertsen] (Zebra 0-8217-2313-8,
Mar ?88 [Feb ?88], $2.95, 286pp, pb) [C.A.D.S.] High-tech
post-catastrophe military novel.
C.A.D.S. # 6: Tech Inferno [by Ryder Syvertsen] (Zebra 0-8217-2410-X,
Jul ?88, $2.95, 255pp, pb) [C.A.D.S.] Post-holocaust adventure novel.
Men in fighting suits battle the evil communists.
C.A.D.S. # 7: Doom Commander [by Ryder Syvertsen] (Zebra
0-8217-2685-4, Jun ?89 [May ?89], $2.95, 220pp, pb) [C.A.D.S.]
Post-holocaust military sf novel.
C.A.D.S. # 8: Cybertech Killing Zone [by Ryder Syvertsen] (Zebra
0-8217-2818-0, Oct ?89, $2.95, pb) Post-holocaust military sf novel.
C.A.D.S. # 9: Suicide Attack [by David Alexander] (Zebra
0-8217-2926-8, Mar ?90 [Feb ?90], $2.95, 224pp, pb) [C.A.D.S.]
Post-holocaust military sf novel.
C.A.D.S. #10: Recon by Fire [by David Alexander] (Zebra 0-8217-3147-5,
Oct ?90 [Sep ?90], $2.95, 222pp, pb) [C.A.D.S.] Post-holocaust
military sf novel
C.A.D.S. #11: Death Zone Attack [by David Alexander] (Zebra
0-8217-3374-5, Aug ?91, $3.50, 176pp, pb) [C.A.D.S.] Post-holocaust
military sf novel in an ongoing series.
C.A.D.S. #12: Tech Assassins [by David Alexander] (Zebra
0-8217-3600-0, Dec ?91 [Nov ?91], $3.50, 192pp, pb) [C.A.D.S.]
Post-holocaust military sf novel in an ongoing series."

My Google search strategy:

Google Web Search: cads "john sievert"
://www.google.com/search?hl=en&q=cads+%22john+sievert%22

I hope this is the correct series. If not, please request
clarification, and I'll be glad to offer further assistance.

Best regards,
pinkfreud

Awsome.. exactly what I wanted =)

Scary part is you knew to search for cads and john Sievert.

/giggle

I thought I was vauge on the post

Thank you very much for the five stars and the nice tip! Your
description wasn't vague, since I'm familiar with the series.
"Acronym" and "mech suits" were all I needed.

~pinkfreud