I disagree with you completely about USA being better attackers than defenders, if anything, defense is our one true strength and what year after year keeps us in ball games we otherwise have no business winning.
To be sure, our defense looked pretty bad, but I think that is not our defenses' fault, its the difficulty of the Group we played in.
Think about this, we held Germany to its lowest scoring match in YEARS, we held a potent Ghanian team to only one goal, and ALMOST held Portugal to one goal.
When you say our defense looked better pressing high rather than in front of our own goal, I disagree, some of our best stops and saves obviously came in front of our own goal and they WEREN'T made by Tim Howard, so clearly guys got it down when it counts. I think YOU ARE right that we shouldn't ONLY be doing this, rather we should ADD to our goal line defense some more attacking when available and definitely press a bit higher on the pitch to thwart Belgium's offense. You are totally right, when Beasley, Dempsey, Zusi, or most pleasantly surprisingly Jermaine Jones are on the attack, their speed has been hard for other teams to catch up, but time and time again, especially against Ghana and Germany (great defensive teams) our attacks got to crazy and we lost control of the ball before we could shoot or we lost control and defenses were able to get set and get a save.
While tactically you may be looking for USA defense to do more to stop opponents attacks (which to be sure we didn't), or to get more takeaways (which to be sure we need to do against Belgium), or simply to otherwise limit opponents finesse yeah, our defense looked sloppy. BUT the results speak for itself, speak what you will about Italy's defense but USA is the one advancing and again, we did it ALL on defense considering Ghana and Portugal tied our goals scored, but we won by having the best goals allowed numbers
