All those incidents, with the notable exception of the September 11 attacks, were committed by American Muslims.
And the constitution does NOT ban Islam. Check that pesky 1st amendment.
Doesn't matter what country. Generally, Muslims DON'T HAVE a country. Their only "country" is the UMMA (worldwide community of Muslims).
As for the 1st amendment, is is totally trumped by the Constitution's Supremacy clause (didn't I just finish telling you that ?) The 1st amendment has numerous exceptions. The Supremacy Clause has NEVER had an exception. NOTHING can be supreme over the Constitution - including religions (which Islam in not eve a religion anyway)
Radical Islamic terrorism is to Islam as the KKK is to Christianity.
Both have high jacked one of the great faiths of this world to serve a vile and evil purpose. Both groups employ symbols, scriptural writings and religious zeal to impose their twisted will on a population that does not support the means nor the ends.
Attitudes such as yours only makes it easier to repress, subjugate and eventually eliminate those who hold a different faith than your own. Much as the Nazis treated the European Jews.