The Obama administration says it is still trying to determine whether ISIS was behind the attack in Garland, Texas, in which two terrorists were shot dead after trying to kill people attending a “draw the Prophet Muhammad” contest. ISIS is not only claiming responsibility, but promising new attacks.

On anonymous message board JustPasteIt, a group that identified itself as ISIS posted its intentions: “The attack by the Islamic State in America is only the beginning of our efforts to establish a wilayah (governing province) in the heart of our enemy. Our aim was the khanzeer (swine) Pamela Geller and to show her that we don’t care what land she hides in or what sky shields her; we will send all our Lions to achieve her slaughter. … To those who protect her: this will be your only warning of housing this woman and her circus show. Everyone who houses her events, gives her a platform to spill her filth are legitimate targets. We have been watching closely who was present at this event and the shooter of our brothers. We knew that the target was protected. Our intention was to show how easy we give our lives for the Sake of Allah.”

That’s pretty straightforward. The Islamic State “Trojan Horse” is among us, as clear thinkers always knew would happen. Infiltrating one’s enemy and undermining him from within is an old and sometimes successful tactic. In the post, ISIS claims to have “71 trained soldiers in 15 states,” naming five of them — Virginia, Maryland, Illinois, California and Michigan. It says, “23 have already signed up for missions.”

We have long since passed the point of no return when it comes mollifying Islamic fanatics. If we are serious about combating this virus, the government is going to have to do some things that may not be palatable to American sensibilities.

First, we must stop thinking that the extremists want our way of life — freedom, pluralism and tolerance. They don’t. To the extent too many in our leadership continue to embrace this false faith, we only give encouragement to our enemies that they can win and that this is their moment to bring down the “great Satan.”

Second, those mosques and Islamic schools that teach hate and preach the destruction of America must be closed and never reopened. Some have gone beyond First Amendment protection to practice sedition, which Wikipedia defines as “overt conduct, such as speech and organization, that is deemed by the legal authority to tend toward insurrection against the established order. Sedition often includes subversion of a constitution and incitement of discontent (or resistance) to lawful authority.”

Does this not define what ISIS is doing by inciting and recruiting home-grown terrorists to commit destruction against America?

Third, we must not allow any more refugees or immigrants from countries populated by Islamic extremists.

The FBI says one of the terrorists killed in the shootout with security guards in Texas has been on their radar screens for years. Were they forced to wait until he acted before they could arrest him? If so, perhaps our laws need updating to allow law enforcement to take pre-emptive action against people who visit radical Islamic websites or engage in other behavior consistent with terrorist behavior.

If the ISIS posting is to be believed (and why shouldn’t it?), we are being set up for possible multiple attacks that will cause death, destruction and panic in this country, along with damaging economic reverberations.

Now would be a good time to hear from our elected officials — and the presidential candidates — about what they intend to do to fight and win this war, which is quickly moving to American soil.

Readers may email Cal Thomas at tcaeditors@tribpub.com.