They were stars -- on college radio

The girls and I listened to THE ALARM compilation "STANDARDS" as we drove to the airport late last night to pick up my wife JILL, who had spent a week in Florida during a sales meeting.
The Rhyl, Wales band were somewhat of an anomaly: In many instances, they actually charted higher on the U.S. COLLEGE RADIO CHARTS -- that early barometer of alternative music -- than on their native U.K. singles chart.
"The Stand," for example, reached a mere 86 on the U.K. chart, but soared to No. 9 on the college radio chart.
Other notable alternative hits included "68 Guns" (No. 5 college radio, 17 U.K.), "Spirit of '76" (15 and 22), "Rain in the Summertime" (2 and 18) and "Sold Me Down the River" (4 and 43).
The classic example of The Alarm's success in the American underground is "Strength." It spent three weeks atop the U.S. college radio chart in 1985, but only reached No. 40 in the U.K.
I thought about the disparity as the girls and I listened to "Strength" last night. What was it about The Alarm that created much more demand among American alternative music fans?
Perhaps The Alarm were too anthemic for mainstream British tastes at the time? Perhaps their Welsh version of stadium rock was squeezed out of contention by the likes of U2 (Ireland) and Simple Minds (Scotland)?
I am still wondering why The Alarm were only "huge" on such a relatively small scale.