Ok, suggested next paragraph (if it's good, copy & paste it to the page):

Generally, rigidly sticking to a pure implementation of either strategy is a bad idea. A passive strategy is very hard to pull off if your opponent goes for an aggressive strategy, particularly if you start the game with low resources.

Being Passive

To protect an area of any workable size requires a considerable number of defensive structures, particularly if you're placed on a plain, rather than with one side of your base buttressed against a natural barrier. With low resources (and the outlay on a least a few metal extractors & solar collectors, along with a unit producing structures) you'll quickly stall your construction of lasers (or similar, depending on your mod). This will leave you with at least one approach to your base totally unprotected and with your commander (most probably your only mobile unit with a weapon) still struggling to build a laser on the other side of your base. Now, you may strike it lucky and the open hole will be on the side of your base where the attack doesn't come from. An AI opponent will likely keep throwing units from the same direction (and hence at your towers) which will allow you to know where they are and reinforce that side of your defences. Any human player, however, will more than likely skirt around your base and find the open side and go for the jugular. You'll lose the soft centre of your base, cease to have anything but lasers (and now effectively nil income to do anything with) leaving you a sitting duck to be picked off later.

Against an aggressive Human player, a passive player, unless (s)he is on a very large map will almost always lose. Against an AI the human player has a chance to win - experience will help here, if you know where the start locations are, you know where the attack will come from.

The other disadvantage is that a passive strategy alone is unlikely to be able to win the game for you. Even if you do beat the initial attack back, having spent your resources on defensive structures, you won't have resources to actually build units for a counter attack. The only chance of this is if you can spare construction units to keep your expansion up with the opposition player and reclaim the corpses of his/her units to put the balance of resources in your favour. This will obviously not be possible if you had to use the D-Gun to win the initial engagement. The best you can hope for is to create a short-term stalemate, predict your enemy's attack plan to build concentrated defences against it and hope to tool up with the right equipment (i.e. stuff the enemy has no defence against) and deal a powerful blow in the next round of engagements. Unfortunately, even if you build an impenetrable defence, this is still not a sure path to victory. Unlike the vast majority of other RTS games, Total Annihilation-derived games do not have finite resources - you can't build a low cost / high effectiveness defence and just let the enemy expend all the resources on the map throwing units at it, before making a (relatively) small counterattack on an undefended base for an easy win. There is effectively no cap on the quantity of resources that can be gathered per second. If you're building defensively you can only assume that the strength of attacks will increase each time. This gives you only one option that will allow you to win. Use the safety of your base to develop advanced resource and unit technologies to allow you to make decisive blows at the enemy's ability to attack you. Given that, with you bottled up in your base, your enemy has the entire map to themselves, it is much harder for you to do this and win. Games that go this way often end in nuke-slinging matches. Your ability to do this will likely be influenced by the mod you are playing, depending on whether the mod maker wants you to be able to play in this style 'free resources' structures (such as fusion plants/moho metal makers) will be more or less effective. For instance, this strategy is quite hard to pull off in Absolute Annihilation.

The primary advantage of this tactic is that, assuming that you don't get killed on the first wave, it's fairly easy to not lose (against an AI). If all your interested in is a bit of explosive mayhem for a few hours to entertain you and are quite happy to end the game prematurely then this is most guaranteed to keep the game going - it's a lot easier to force a stalemate by building up more defences than the enemy is likely to penetrate and then sit around that to try and keep pitched battles even. Once you've built your defence, it's also fairly easy to maintain as repair units can be set to patrol an auto-repair the occasional bit of damage, and you can go and get some coffee without having to pause the game.

being aggressive

<someone else write this - I'm a porcer>