Is the true Jewish ideal to sit and learn Torah all day? What about when it's at the expense of earning a living and, in Israel at least, defending your country? When did the "kollel life" become the norm and not the exception? Didn't our ancestors, even from the time of the Bible, fight battles and hold down jobs?

No one questions the special place that learning Torah has in a Jew's life.  Torah is what guides our actions and shapes our thoughts so that we "think like Jews." It molds our observance and improves our conduct, all of course in measure to the person learning it. It brings blessing into the world for everything: peace, prosperity, and even....to win wars.

At the same time, a Jew is supposed to work.  The Gemara in Berachot tells us that only a select few are permitted to dedicate themselves to full time learning while most people need to get a job.  The Ben Ish Hai in Birkat Avot says that it is even forbidden for someone not in this select group to refrain from working.  An extensive treatment of the Jewish work ethic can be found in Dr. David Schall's By the Sweat of Your Brow.

So what about now, when 65% of men identified as Haredi Orthodox Jews in Israel don't work?  Something about the current reality doesn't seem to fit with this picture.

The answer is actually more sociopolitical than religious.  At the beginning of the State of Israel, the Torah community was decimated from WWII and was also under assault from the secular Zionist regime whose goal was to create a new secular Israeli identity to replace the traditional Jewish.  However, the leaders of the movement such as David Ben Gurion recognized the legitimacy Torah gave to his position and the right of Jews to be in Israel at all.  It was at this point when Ben Gurion negotiated the so-called Status Quo with the Haredi leader Rabbi Avrohom Yishaya Karelitz, also known as the Hazon Ish. The Status Quo is what has allowed Haredim to opt to learn Torah instead of going to the army, an exemption at the time that only applied to about 100 people and one that Ben Gurion was comfortable giving since he believed that Orthodox Judaism was in his death throes anyway and the exemption wouldn't be needed in a generation or two.

It didn't work out that way.   Haredi leaders mobilized the community to get anyone who could sit and learn to sit and learn, and to take money in order to do so.  The only vague parallel to this is drawn from the relationship of Yissachar and Zevulun, the two sons of Jacob who arranged that Yissachar would learn while Zevulun would support him financially.  This relationship did happen historically, but no precedent existed at to that point that would enable to do it against the will of the financer.  The situation is called a horah sha'ah, a necessary response to a timely difficult situation.

Jews always worked.  Jews always used to learn two.  Now we have a split of two camps where neither respects what the other is doing, and the dominant culture is attempting to force their way of life on the minority.  Or is it the minority who's forcing the majority?  It really depends on who you talk to.  Either way, kollel culture will continue in its current incarnation as long as there is a perceived assault against Torah values and that the entire mantle of learning is thrust upon the few.

There is another concern to keep mind of.  Let's say the Roshei HaYeshiva do tell 75% of their students to go to the army and then to work.  Who are they going to be?  What will that do to these people and their families when they are ruled to not be good enough to make the cut?  How can someone assess the relative value of one person's learning to another's?

Those who sit and learn are contributing, every last one of them.  The question is how much and would they be contributing more in a different capacity.  Fifty years ago, the answer was there is no place better for any of these people to be.  Now it is not so simple, but everyone wants easy answers to difficult questions.