The Vilna Gaon points out there are only two mitzvot that one does with ones entire body. They are the mitzvot of Succot and being in G-ds beloved garden otherwise known as Israel. There are other factors however, that uniquely unite these two mitzvot.
Both these mitzvot are only done by those with faith in G-d. Perhaps this explains the gemorah that states those outside G-ds beloved garden worship idols in purity. Anyone outside G-ds beloved garden is de facto saying with his or her entire body that they either do not have enough faith in G-d to sustain them or that they think that they are in fact G-d. Being religious is not wearing the appropriate clothing and using the appropriate words. Being religious is doing what G-d wants even when it seems silly or against common sense.
Why does G-d deem it so important for a person to be in a tent for 7 days? There is no substantial difference between being outside or inside other than is placing oneself in the place that G-d decides He wants His people to be. This is the same situation with being in G-ds beloved garden. One palm tree in Israel looks like any palm tree in Miami. G-d however is testing His beloved people if they listen to what He wants or they decide that they are really G-d and are able to calculate which mitzvah is better.
Rav Meir Kahane would explain that the term “Chillel Hashem” literally means “G-d in space”. One does this when one decides on ones own to do mitzvot because they decide they “like it” or “want it.” This thereby puts G-d into space and replaces Him with those that do mitzvot because they agree with them or like them rather than because they have a direct order.
Any religious Jew that pays the slightest attention to their religion be it their prayers or Torah portion of the week will see how much G-d loves His beloved garden. One who therefore truly loves G-d will want to come to G-ds beloved garden and fight for it. Giving an example on this if one knows ones mother loves chocolate one will not buy her flowers for her birthday. So too a religious Jew will not want to stay outside G-ds beloved garden learning Torah if one knows that our mother really prefers us living in G-ds beloved garden.
It should be stressed that while there are legitimate exceptions for Jews not to be here or for Jewish men not to join the Israeli Defense Forces (Tzahal) they are the extreme exception. Women while not permitted halachicly to join Tzahal can do other things such as not being afraid to walk through Arab neighborhoods or ride busses thereby showing that this land still belongs to the Jews. It also needs mentioning that while there is a halachic exemption for Torah scholars not to join the army that exemption only applies during what is termed milchemet rishut (voluntary wars). What we have in the world of today is halachicly termed a milchemet mitzvah (mandatory war) where everyone goes including a groom from his own wedding.