On one hand, I understand why there is resistance to having certain school personnel being armed. But it does make sense, and I do not (on the other hand) understand the resistance to armed guards or armed personnel in the schools.

NO ONE is talking of a FORTRESS - the NRA is calling for armed guards, think of it as an increase in the jobs program.

I believe Bill Clilnton instituted an armed guard program (one guard may not be enough).I guess Clinton was kind of cuckoo to turn schools into fortresses???  Actually Clinton did more than that (adding 100K policemen nationwide) He wanted security in the schools as well as dealing with mental health and troubled youth.

From the White House Accomplishments of President Clinton  : 

President Clinton's Safe and Drug Free Schools and Community Act and the Safe Schools Act provide funding to schools to fight violence and drug abuse. Schools can use up to 25 percent of their funds to purchase metal detectors, develop safe zones, and hire school security personnel.

Years later we still haven't dealt with the issues in a way that prevents shootings  Although Clinton called for prevention and identification of troubled youth.

 Here is Clinton's address  right after Columbine and it is one time that this conservative respected his speech. 

Here is Clinton's video speech (state of union)   upholding the assault weapon ban... That didn't stop Columbine from happening years later.

My understanding is that Obama has cut these programs to the schools..Financially maybe that makes sense... .the states scrambling for educational dollars never made sense to me either.

History is useful for learning from.  For one thing the armed guards at COLUMBINE did help. I remember when it was thought that they PREVENTED many more kids from dying.

 Of course it is repulsive but we have armed guards in shopping malls (in AZ on horseback even).   We have camera's that spy on us everyday.  The schools several years ago instituted metal detectors, and there are searches of backpacks when necessary - remember why?  Many schools have lock down and students can't leave campus unless they are seniors because of lunch time traffic accidents. Many schools are already like prisons.  Or from a different viewpoint they are safer environments that promote learning, freer from fear of a fellow student taking a gun or knife and killing another.

Facts are sometimes we have to do things we don't want to do - to ensure MORE safety... not complete safety --- as that will never happen.