We hear the term “game changer” from time to time.

It refer to events that might be decisive in determining the result of, say, a struggle.

I heard the term today in a National Public Radio interview about Turkey’s decision to (a) allow U.S. aircraft to fly into Syria and Iraq from Turkish air bases and (b) actually strike the Islamic State forces with its own combat aircraft.

Welcome to the fight, Turkey.

The Turks could become the most important ally the United States in this fight against the Islamic State.

It belongs to NATO. It is a military powerhouse with a sophisticated air and ground military force.

And as of a few days ago, it now has suffered grievously at the hands of ISIL forces. A suicide bomber detonated an explosive in a Turkish portion of Kurdistan, killing more than 30 victims. The Turks, therefore, now have skin in this game.

Turkey had been a reluctant ally up to this point, denying U.S. requests to use its bases to launch attacks against ISIL installations in nearby Syria and Iraq. The Turks’ agreeing to allow access to these bases gives our air power a distinct new advantage as it continues its bombing barrage against ISIL.

What’s more, the Turks have engaged ISIL themselves, sending jets on bombing sorties against ISIL strongholds.

OK, does this mean the end of ISIL is in sight, that the fight is nearly over?

No. It does mean, however, that we now have an important ally on our side willing — for the first time — to engage the enemy face to face.

Welcome aboard, Turkey. Let’s hope this development, indeed, is a game changer.