correspondent greg palkot tells us where things stand tonight. >> has the u.s. taken one step closer in being involved in a clash between china and the island of taiwan. president biden appeared to last night. >> i don't want a co-war with china. i just want to make china understand that we are not going to step back. we are not going to change any of our views. >> are you saying that the united states would come to tijuana's defense. taiwan's defense. >> yes we have a commitment to do that. >> seen chinese military aircraft enter their region cited u.s. rock solid support. china was also quick to react. >> we urge the u.s. to be cautious with its words and actions on the taiwan issue. and not to send any wrong signals. >> america's taiwan relations act is purposefully vegas vaguee u.s. shall make available to taiwan service was in such quantity as may be necessary to enable taiwan to maintain a sufficient self-defense capacity. experts say tampering with a