During his speech, Scott Walker declared that the only way to defeat ISIS is to overthrow the government of Bashar al-Assad.
He also added that in order to defeat ISIS, the US will have to recruit and support those fighters in Syria who are against both ISIS and Assad.
Air strikes on ISIS in Syria were authorized by the Obama administration. However, Republicans and Democrats are looking for a stronger response to the terrorist group.
In addition to this, Russian military personnel have arrived in Syria. It is believed that the Russian presence in Syria will alter current dynamics in the Middle East. Russian pilots will be flying combat missions in Syria.
In case the US implements hostile posture against the Syrian government, Russian military might respond to that.