DerechHamelech and Akuperman,
Are you seriously suggesting that the IDF is not preventing a wholesale slaughter of the Jews in Eretz Yisroel? Maybe if the Zionists had never returned, we could live in relative peace (i.e. just second-class citizens). But they did and now, 80 years later the only thing -outside of nissim which one cannot rely on- that is protecting the Jews of Israel is the IDF. The aggadata from the Yerushalmi is making a theological point, it is not suggesting that armies are unnecessary or somehow endanger the people they are designed to protect.
When we say the zechus of Torah learning protects us we do not mean that it creates ananei hakovod to catch missiles. We mean that it provides the zchus that allows the IDF to be successful.
Yes Talmud Torah is keneged kulam, but that is in terms of schar not in terms of what takes precedence. Would you hold that it is assur for a Ben Torah to be in Hatzoloh or Zakah? Is it assur for a Ben Torah to leave kollel to get a job to support his family?
We are not suggesting kollelim should be abolished, chas v’shalom, nor are we suggesting that chareidim who serve in the army should not learn every day. We are merely suggesting that chareidim take some of the burden in risking their lives for the protection of their fellow Jews.